Related
I'm working on the last exercise of the "Think like a computer scientist, C version" book and I have some trouble with one particular point.
The exercise consists of making a small game, where the computer picks a random value between 0 and 20 and then asks me to guess the number.
After that, the computer counts the number of tries I made and, if I get a better score than the previous party, I need to store my name and the number of tries in a structure.
My problem is the following: When I restart the game, the string value, player_name, in the structure gets somehow deleted but player_score is still there.
First, I made a "call by value" function to create the structure and then a tried with a "call by reference" but getting the same results.
I think I tried everything I could with my actual knowledge for now; so, if someone could check my code and give me some tips about what's wrong I would much appreciate it!
//HEADERS
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define FALSE 0
#define TRUE 1
//TYPEDEF STRUCTS
typedef struct
{
int player_score;
char *player_name;
} HS_Player;
//FUNCTION PROTOTYPES
int Random_Value(void);
int Get_User_Choice(void);
int Check_Result(int computer, int my_choice);
int Try_Again(int game_result, int computer);
void Player_Infos(HS_Player *player_p, int score);
int Game_Restart(void);
//MAIN
int main(void)
{
int end_game;
int high_score_value = 100;
HS_Player player;
while (end_game != TRUE)
{
int computer_number = Random_Value();
printf("Guess the number between 0 et 20 chosen by the computer.\n");
int your_number = Get_User_Choice();
int result_game = Check_Result(computer_number, your_number);
int tries_to_win = Try_Again(result_game, computer_number);
printf("Number of tries: %i\n", tries_to_win);
if (tries_to_win < high_score_value)
{
Player_Infos(&player, tries_to_win );
high_score_value = player.player_score;
}
printf("Highest score: %i By: %s\n", player.player_score, player.player_name);
printf("\n");
end_game = Game_Restart();
}
return EXIT_SUCCESS;
}
//Random_Value FUNCTION
int Random_Value(void)
{
srand(time(NULL));
int x = rand();
int y = x % 20;
return y;
}
//Get_User_Choice FUNCTION
int Get_User_Choice(void)
{
int success, x;
char ch;
printf("Your Guess:\t");
success = scanf("%i", &x);
while (success != 1)
{
printf("Your input is not a number. Please try again:\t");
while ((ch = getchar()) != '\n' && ch != EOF);
success = scanf("%i", &x);
}
if (x < 0 || x > 20)
{
printf("Your input must be between 0 and 20. Please try again.\n");
Get_User_Choice();
}
return x;
}
//Check_Result FUNCTION
int Check_Result(int computer, int my_choice)
{
int check_result;
if (my_choice < computer)
{
printf("Computer number is larger!\n");
check_result = FALSE;
}
else if (my_choice > computer)
{
printf("Computer number is smaller!\n");
check_result = FALSE;
}
else if (my_choice == computer)
{
printf("It's a Match! You chose the same number than the computer.\n");
printf("\n");
check_result = TRUE;
}
return check_result;
}
//Try_Again FUNCTION
int Try_Again(int game_result, int computer)
{
int tries_befor_success = 1;
while (game_result != TRUE)
{
int your_number = Get_User_Choice();
game_result = Check_Result(computer, your_number);
tries_befor_success++;
}
return tries_befor_success;
}
//Player_Infos FUNCTION
void Player_Infos(HS_Player *player_p, int score)
{
char new_name[80];
printf("Congrats! Your made a new high score.\n");
printf("What's your name ?\t");
scanf("%s", new_name);
printf("\n");
player_p->player_score = score;
player_p->player_name = new_name;
}
//Game_Restart FUNCTION
int Game_Restart(void)
{
int quit_value;
printf("Quit Game ?\n");
printf("Press 'y' to quit or any other keys to continue.\n");
fflush(stdin);
char quit_game = getchar();
printf("\n");
if (quit_game == 'y')
{
quit_value = TRUE;
}
else
{
quit_value = FALSE;
}
return quit_value;
}
The problem is that, in your Player_Infos function, you are assigning the address of a local array to the char* player_name pointer member of the passed structure. When that function ends, the local array it used will be deleted and the pointer in the structure will be invalid. (In the case of the player_score, you don't have that problem, because the given value is copied to the structure member.)
There are several ways around this; one would be to use the strdup() function to make a copy of the local char new_name[80]; array – but that is really overkill, and you would need to manage (i.e. free()) that allocated string whenever you make a modification.
A simpler way is to make the player_name member an actual array of char and then use strcpy() to copy the local array into that member.
Better, still, with the player_name member defined as char [80], you can read directly into that (in the function), and avoid the local array completely:
typedef struct
{
int player_score;
char player_name[80];
} HS_Player;
//...
void Player_Infos(HS_Player *player_p, int score)
{
printf("Congrats! Your made a new high score.\n");
printf("What's your name ?\t");
// Read directly. Limit input to 79 chars (allowing room for null terminator).
scanf("%79s", player_p->player_name);
printf("\n");
player_p->player_score = score;
}
Also, just as a "style" tip, you may want to change the member names to just score and name, as the "player" part is implied by the structure type-name itself.
This issue you are having is that you are associating the player name pointer to a variable that goes out of scope when you leave the "player_Infos" function. What you probably would want to do is define the name as a character array in your structure and then use the "strcpy" call in your function instead. Following is a couple of code snippets illustrating that point.
//TYPEDEF STRUCTS
typedef struct
{
int player_score;
char player_name[80];
} HS_Player;
Then, in your function, use the "strcpy" call.
//Player_Infos FUNCTION
void Player_Infos(HS_Player *player_p, int score)
{
char new_name[80];
printf("Congrats! Your made a new high score.\n");
printf("What's your name ?\t");
scanf("%s", new_name);
printf("\n");
player_p->player_score = score;
strcpy(player_p->player_name, new_name);
//player_p->player_name = new_name;
}
When I tested that out, I got a name to appear in the terminal output.
Computer number is smaller!
Your Guess: 4
It's a Match! You chose the same number than the computer.
Number of tries: 8
Highest score: 4 By: Craig
FYI, you will need to include the "string.h" file.
Give that a try.
Name Update
The reason your player.player_name is not getting updated is because you can't assign a string this way in C. When doing player_p->player_name = new_name; you're actually saving in player_p->player_name the memory address of new_name.
Instead, what you want to achieve, is to copy each character of new_name to player_p->player_name and in order to achieve this, you have to change the type of prlayer_name field from char* player_name to char player_name[80], then assign it using, for example, strcpy():
#include <string.h>
// [...]
//TYPEDEF STRUCTS
typedef struct
{
unsigned int player_score;
char player_name[80];
} HS_Player;
// [...]
//Player_Infos FUNCTION
void Player_Infos(HS_Player *player_p, int score)
{
char new_name[80];
printf("Congrats! Your made a new high score.\n");
printf("What's your name ?\t");
scanf("%s", new_name);
printf("\n");
player_p->player_score = score;
strcpy(player_p->player_name, new_name);
}
Data Persistence
To make data (players info) persistent over multiple runs, you have to save the content of the struct to a file.
Example
int Save_Score(char* filename, HS_Player* player)
{
FILE* file = fopen(filename, "w");
if (file == NULL)
{
fprintf(stderr, "\nAn error occurred while opening the file\n");
return -1;
}
if (fprintf(file, "%d %s", player->player_score, player->player_name) < 0)
return -1;
fclose(file);
return 0;
}
int Load_Score(char* filename, HS_Player* player)
{
FILE* file = fopen(filename, "r");
if (file == NULL)
{
fprintf(stderr, "\nAn error occurred while opening the file\n");
return -1;
}
if (fscanf(file, "%d %79s", &player->player_score, player->player_name) < 0)
return -1;
fclose(file);
return 0;
}
so this is part of a kind of menu, the only problemis that the word is not getting into the array "frase" i have already tried with frase [ ] = "the word" but idk why it wont work
if(lvl==1)
{
printf("lvl 1\n");
if (opc==1)
{
printf("Animales\n");
a = rand() %3 + 1;
printf("%d", a);
if (a=1)
frase <= "pato";
if (a=2)
frase <="ganso";
if (a=3)
frase <= "avispa";
}
if (opc==2)
{
printf("comida\n");
a = rand() %3 + 1;
if (a=1)
frase <="pasta";
if (a=2)
frase <="pizza";
if (a=3)
frase <="pastel";
}
if (opc==3)
{
printf("paises\n");
a = rand() %3 + 1;
if (a=1)
frase <="peru";
if (a=2)
frase <="brasil";
if (a=3)
frase <="egipto";
}
}
`
I suggest you solve this by modeling your data. In this case with a array of structs. Then you index into to obtain the relevant data:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
int main() {
struct {
const char *opc;
const char **frase;
} data[] = {
{"Animales", (const char *[]) { "pato", "ganso", "avispa" }},
{"comida", (const char *[]) { "pasta", "pizza", "pastel" }},
{"paises", (const char *[]) { "peru", "brasil", "egipto" }}
};
srand(time(0));
int opc = rand() % 3;
printf("lvl 1 %s %s\n", data[opc].opc, data[opc].frase[rand() % 3]);
return 0;
}
If you have a lot of data put the data in a file and write a function to build the struct at start-up. A special case of this approach is to store the data in a lightweight database like SQLite, then you can query for the relevant data at run-time or load it all it upon start-up.
You many no longer need to copy the frase, but if you want to use a strcpy:
char frase[100];
strcpy(frase, data[opc].frase[rand() % 3]);
Multiple things to be improved in the code. The if(a=1) should be changed to ==. Not sure what you mean by frase<="pato", strcpy or strncpy should be used. Please refer the following sample code.
void copytoarray(char *array, char *word, unsigned int len)
{
if(array == NULL || word == NULL)
{
return;
}
strncpy(array, word, len);
}
int main(void) {
char frase[15] = {'\0'};
int a, lvl =1;
int opc =1;
if(lvl==1)
{
printf("lvl 1\n");
if (opc==1)
{
printf("Animales\n");
a = rand() %3 + 1;
printf("%d\n", a);
if (a==1)
copytoarray(frase, "pato", strlen("pato"));
if (a==2)
copytoarray(frase, "ganso", strlen("ganso"));
if (a==3)
copytoarray(frase, "avispa", strlen("avispa"));
}
}
printf("Word: %s\n ",frase);
}
/* Created Library File */
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <assert.h>
#include <string.h>
#include "tournament.h"
Team * initializeTeam(char * name, Player * players){
Team *team = malloc(sizeof(Team));
(*team).name = name;
(*team).players = players;
return team;
}
Team * game(Team * team1, Team * team2){
int turns = 10;
int team_A_total = 0;
int team_B_total = 0;
int team_A_shooting = 0;
int team_B_shooting = 0;
int team_A_blocking = 0;
int team_B_blocking = 0;
int team_A_def = 0;
int team_B_def = 0;
int team_B_off = 0;
int team_A_off = 0;
for(int i=0;i<turns;i++){
team_A_off = team_A_off + (*team1).players[i].offensive;
team_A_def = team_A_def + (*team1).players[i].defensive;
team_B_off = team_B_off + (*team2).players[i].offensive;
team_B_def = team_B_def + (*team2).players[i].defensive;
};
for(int j=0;j<turns;j++){
team_A_shooting = rand() % team_A_off;
team_A_blocking = rand() % team_A_def;
team_B_shooting = rand() % team_B_off;
team_B_blocking = rand() % team_B_def;
if(team_A_shooting>team_B_blocking){
team_A_total = (team_A_total + 1);
};
if(team_B_shooting>team_A_blocking){
team_B_total = (team_B_total + 1);
};
};
if(team_A_total > team_B_total){
return team1;
}
else
if(team_B_total > team_A_total){
return team2;
}
else
if(team_A_total == team_B_total){
int number = rand();
if(number % 2 == 0){
return team1;}
else{
return team2;}
}
return 0;
}
/*header file*/
#ifndef JG_TOURNEY_H
#define JG_TOURNEY_H
typedef struct Player{
int offensive;
int defensive;
int number;
int team;
char first[255];
char last[255];
} Player;
typedef struct Team{
char * name;
Player * players;
} Team;
Team * initializeTeam(char * name,Player * players);
Team * game(Team * team1, Team * team2);
Team * tournament(Team **, int);
void deleteTeam(Team *);
#endif
/*Driver code*/
#include"tournament.h"
#include"tournament.h"
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <assert.h>
#include <string.h>
#define DEBUG 0
#define NUM_TEAMS 32
#define NUM_PLAYERS 10
Player * draftPlayers(char * filename, int team, int num_players);
int inLeague(Team *, Team **);
int main(){
/***** Change the team names to names of your choosing ******/
char * team_names[] = {
"team1",
"team2",
"team3",
"team4",
"team5",
"team6",
"team7",
"team8",
"team9",
"team10",
"team11",
"team12",
"team13",
"team14",
"team15",
"team16",
"team17",
"team18",
"team19",
"team20",
"team21",
"team22",
"team23",
"team24",
"team25",
"team25",
"team27",
"team28",
"team29",
"team30",
"team31",
"team32",
};
/********************************************************************/
/* DO NOT ALTER ANY OF THE THE DRIVER CODE BELOW */
/********************************************************************/
#if !DEBUG
fclose(stderr);
#endif
printf("\t-----------------------------------\n");
printf("\t- Creating Your League -\n");
printf("\t-----------------------------------\n");
srand(time(NULL));
printf("\n\t=========Test #1: Creating your Teams and Players===========\n\n");
Team ** league = malloc(sizeof(Team*) * NUM_TEAMS);
//create teams i.e. league of N teams.
for(int counter = 0; counter < NUM_TEAMS; counter++){
Player * draft = draftPlayers("players.dat", counter, NUM_PLAYERS);
assert(draft[0].team == counter%NUM_TEAMS);
league[counter] = initializeTeam(team_names[counter], draft);
assert(sizeof((league[counter]->players[rand() % NUM_PLAYERS])) == sizeof(Player));
assert((league[counter]->players[rand() % NUM_PLAYERS]).offensive > 0);
assert((league[counter]->players[rand() % NUM_PLAYERS]).defensive > 0);
assert(sizeof(*(league[counter])) == sizeof(Team));
}
printf("\n\t\t....League Initialized\n");
printf("\t-----------------------------------\n");
printf("\t- Part 1: Exhibition Games -\n");
printf("\t-----------------------------------\n");
printf("\n\t=========Test #1: Sanity check for the game===========\n\n");
Team * winner = game(NULL, NULL);
assert(winner == NULL);
printf("\n\t\t....Test Passed\n");
printf("\n\t=========Test #2: Playing a Game between two random teams===========\n\n");
Team * team1 = league[rand() % NUM_TEAMS];
Team * team2 = league[rand() % NUM_TEAMS];
printf("Up next, an exhibition game between %s and %s\n", team1->name, team2->name);
winner = game(team1, team2);
assert(winner == team1 || winner == team2);
printf("The winning team is %s\n\n", winner->name);
printf("\n\t\t....Test Passed\n");
printf("\n\t=========Test #3: Playing a Game between the same team===========\n\n");
int team_num = rand() % NUM_TEAMS;
printf("Up next, a a scrimmage for %s\n", league[team_num]->name);
winner = game(league[team_num], league[team_num]);
assert(winner == league[team_num]);
printf("The winning team is %s\n\n", winner->name);
printf("\n\t\t....Test Passed\n");
When running the created library file and running it with the driver code I fail the first test because of a segmentation fault. I know it has to do with something with my memory however I am unable to figure out where my code is causing this. I know it is a lot if code to deal with however I only included the parts of the code that is needed to run this test. Any help is very much appreiated.
(*team).name = name;
(*team).players = players;
It looks like you're trying to dereference team using *, then dereference it again using .name, so try removing the * and dereference with .name or ->name only.
I am making a "Clicker-Game". It's my first real game that I'm doing alongside school. I got all of the game code complete but I want to have a loop in the background that adds geldps(money per second) after every second.
I tried threads but I don't really understand it and we won't learn that until next year, so I´m asking, if anyone can either tell me a better way to make a loop in the background that runs independent from the main program, and can just add geldps to geld every second. Thanks.
PS: I am sorry for the German variables. Ask me if you don't know what sth means or anything, and it´s probably not very well organised and everything.
#include <stdio.h>
int geldps=0,geld=0;
int main()
{
int stand=0, oil=0, Mine=0, Bank=0,standzahl=100, Minezahl=500, Bankzahl=1000, oilzahl=10000, Werkzeug=0, Werkzeugzahl=10;
char input, input2;
float faktor;
do
{
system("cls");
faktor=1+Werkzeug/10;
printf("%c%c%c%c%c%c%c%c%c%c%c\n",201,205,205,205,205,205,205,205,205,205,187);
printf(" %d$\n",geld);
printf("%c%c%c%c%c%c%c%c%c%c%c\n",200,205,205,205,205,205,205,205,205,205,188);
printf(" Space to get money\n U to go to Upgrades\n Escape to leave");
input=getch();
if(input==32)
{
geld=geld+faktor;
continue;
}
if(input == 117 || input == 85)
{
system("cls");
do
{
system("cls");
printf(" 0 - Tools(10 for 1 more Money)(%d)(%d$)\n 1 - Lemon Stands(%d)(%d$)\n 2 - Mines(%d)(%d$)\n 3 - Banks(%d)(%d$)\n 4 - Oil Refinerys(%d)(%d$)\nBackspace to go back", Werkzeug, Werkzeugzahl, stand, standzahl, Mine, Minezahl, Bank, Bankzahl, oil, oilzahl);
input2=getch();
if(input2== 48)
{
if(geld<Werkzeugzahl)
{
system("cls");
printf("Not enough money(%d/%d$)\n",Werkzeugzahl,geld);
system("pause");
continue;
}
geld=geld-Werkzeugzahl;
Werkzeug++;
Werkzeugzahl=Werkzeugzahl+Werkzeugzahl/10;
}
if(input2== 49)
{
if(geld<standzahl)
{
system("cls");
printf("Not enough money(%d/%d$)\n",standzahl,geld);
system("pause");
continue;
}
geld=geld-standzahl;
stand++;
standzahl=standzahl+standzahl/10;
}
if(input2== 50)
{
if(geld<Minezahl)
{
system("cls");
printf("Not enough money(%d/%d$)\n",Minezahl,geld);
system("pause");
continue;
}
geld=geld-Minezahl;
Mine++;
Minezahl=Minezahl+Minezahl/10;
geldps=geldps+1;
}
if(input2== 51)
{
if(geld<Bankzahl)
{
system("cls");
printf("Not enough money(%d/%d$)\n",Bankzahl,geld);
system("pause");
continue;
}
geld=geld-Bankzahl;
Bank++;
Bankzahl=Bankzahl+Bankzahl/10;
geldps=geldps+10;
}
if(input2== 52)
{
if(geld<oilzahl)
{
system("cls");
printf("Not enough money(%d/%d$)\n",oilzahl,geld);
system("pause");
continue;
}
geld=geld-oilzahl;
oil++;
oilzahl=oilzahl+oilzahl/10;
geldps=geldps+100;
}
}
while(input2!=8);
}
}
while(input!=27);
return 0;
}
update: I was procrastinating and cleaned and improved your code. At the end of this answer.
If all you need is for a number to be consistently incremented based on time, add a function that updates a value based on time.
Here's an example showing not only how to do that but also how to compartmentalize your code into functions and how to use better code formatting and variable names.
#include <stdio.h> // printf()
#include <time.h> // time()
#include <stdlib.h> // random()
#include <unistd.h> // sleep()
int updateValue(int lastValue, int amountPerSecond) {
static time_t lastTime = -1;
time_t currentTime = time(NULL);
int newValue = lastValue;
if (lastTime != -1) {
newValue += amountPerSecond * (currentTime - lastTime);
}
lastTime = currentTime;
return newValue;
}
void seedRandom() {
// Don't use this in production code.
srandom(time(NULL));
}
int sleepRandomly() {
const int SLEEP_RANGE_IN_SECS = 5;
// sleep( 0..5 seconds )
int timeToSleep = random() % (SLEEP_RANGE_IN_SECS + 1);
sleep(timeToSleep);
return timeToSleep;
}
int main() {
const int AMOUNT_PER_SECOND = 5;
int value = 0;
// How many times to run the loop
int numCycles = 5;
seedRandom();
// Initialize the updateValue() start time
value = updateValue(value, AMOUNT_PER_SECOND);
while (numCycles--) {
int amountSlept = sleepRandomly();
int newValue = updateValue(value, AMOUNT_PER_SECOND);
printf("Slept %d seconds.", amountSlept);
printf("Value updated: %10d + (%d secs * %4d amount/secs) = %10d\n",
value, amountSlept, AMOUNT_PER_SECOND, newValue);
value = newValue;
}
return 0;
}
Cleaned up version of your code, and then I just kept improving it.
#include <stdio.h> // printf()
#include <string.h> // strlen()
#include <stdarg.h> // vsnprintf()
#include <unistd.h> // STDIN_FILENO
#include <sys/time.h> // gettimeofday()
#include <time.h>
#include <termios.h>
#include <errno.h>
#include <signal.h>
// TODO: convert the menus to tables:
// key - desc count cost effect
// TODO: add all income sources in a list so it's easy to add more
// without changing code
// TODO: the current pricing is off
// TODO: convert to C++ so we can use classes
// TODO: only use one menu, it's nicer to use
// one global value so we can ensure that we restore
// stdin's terminal settings
struct termios g_oldStdinTermios;
int g_keepGoing = 1;
typedef struct {
int count;
int zahl;
int zahlIncrement;
int geldPerSecondIncrement;
} IncomeSource;
typedef struct {
char lastMessage[100];
// try to avoid global variables, pass them instead
// one variable per line
int geld;
int geldPerSecond;
int geldPerClick;
IncomeSource werkzeug;
IncomeSource stand;
// Use consistent capitalization: sound be "mine"
IncomeSource mine;
IncomeSource bank;
IncomeSource oil;
} Values;
void setLastMessage(Values *values, const char *fmt, ...) {
va_list ap;
va_start(ap, fmt);
(void) vsnprintf(values->lastMessage, sizeof(values->lastMessage), fmt, ap);
va_end(ap);
}
void clearLastMessage(Values *values) {
// clear lastMessage after valid choice
values->lastMessage[0] = '\0';
}
void initializeValues(Values *values) {
clearLastMessage(values);
// use spaces around assignment and operators
values->geldPerSecond = 0;
values->geld = 10000;
// count, cost, cost increment (1/n), geldPerSecond increment
values->werkzeug = (IncomeSource){0, 10, 10, 0};
// BUG: number of stands doesn't increase geld per second
// or geld per click
values->stand = (IncomeSource){0, 100, 10, 0};
values->mine = (IncomeSource){0, 500, 10, 1};
values->bank = (IncomeSource){0, 1000, 10, 10};
values->oil = (IncomeSource){0, 10000, 10, 100};
values->geldPerClick = 1 + values->werkzeug.count / 10;
}
void clearScreen() {
// use ANSI escape sequences
const char *ANSI_MOVE_TO_1_1 = "\x1B[1;1H";
const char *ANSI_CLEAR_SCREEN = "\x1B[2J";
printf("%s%s", ANSI_CLEAR_SCREEN, ANSI_MOVE_TO_1_1);
}
char upcase(char c) {
if (c < 'a' || c > 'z') {
return c;
}
return 'A' + (c - 'a');
}
void setNonBlockingBufferingStdinTermios() {
struct termios new_;
tcgetattr(STDIN_FILENO, &g_oldStdinTermios);
new_ = g_oldStdinTermios;
new_.c_lflag &= ~ICANON;
tcsetattr(STDIN_FILENO, TCSANOW, &new_);
}
void restoreStdinTermios() {
tcsetattr(STDIN_FILENO, TCSANOW, &g_oldStdinTermios);
}
long getElapsedTimeInMs(struct timeval *start) {
struct timeval now;
gettimeofday(&now, NULL);
// in microseconds
long elapsed = ((now.tv_sec - start->tv_sec) * 1000000
+ now.tv_usec - start->tv_usec);
return elapsed / 1000;
}
char getCharacter() {
struct timeval start;
gettimeofday(&start, NULL);
char input = -1;
while (read(STDIN_FILENO, &input, 1) == -1
&& errno == EAGAIN
&& getElapsedTimeInMs(&start) < 500) {
}
return upcase(input);
}
void updateGeld(Values *values) {
static time_t lastTime = -1;
time_t currentTime = time(NULL);
if (lastTime != -1) {
values->geld += values->geldPerSecond * (currentTime - lastTime);
}
lastTime = currentTime;
}
void printHeader(Values *values) {
const char *UPPER_LEFT = "\u2554";
const char *UPPER_RIGHT = "\u2557";
const char *LOWER_LEFT = "\u255a";
const char *LOWER_RIGHT = "\u255d";
const char *HORIZONTAL = "\u2550";
const char *VERTICAL = "\u2551";
updateGeld(values);
// Automatically expand the box as the size
// of geld grows.
const int BORDER_WIDTH = 3;
char geldStr[20];
snprintf(geldStr, sizeof(geldStr), "$ %d", values->geld);
// Move code used more than once into its own function
clearScreen();
printf("%s", UPPER_LEFT);
for (int i = 0; i < (2 * BORDER_WIDTH + strlen(geldStr)); i++) {
printf("%s", HORIZONTAL);
}
printf("%s\n", UPPER_RIGHT);
// use spaces around commas
printf("%s %s %s %s\n",
VERTICAL, geldStr, VERTICAL, values->lastMessage);
printf("%s", LOWER_LEFT);
for (int i = 0; i < (2 * BORDER_WIDTH + strlen(geldStr)); i++) {
printf("%s", HORIZONTAL);
}
printf("%s\n", LOWER_RIGHT);
}
void upgrade(Values *values, IncomeSource *source) {
if (values->geld < source->zahl) {
setLastMessage(values, "Not enough money(%d/%d$)",
source->zahl, values->geld);
return;
}
clearLastMessage(values);
values->geld -= source->zahl;
source->count++;
source->zahl += source->zahl / source->zahlIncrement;
values->geldPerSecond += source->geldPerSecondIncrement;
}
char getUpgradeInput(Values *values) {
clearScreen();
printHeader(values);
printf(" 0 - Tools(10 for 1 more Money)(%d)(%d$)\t\t+%d/click\n",
values->werkzeug.count, values->werkzeug.zahl, values->geldPerClick);
printf(" 1 - Lemon Stands(%d)(%d$)\t\t\t+%d/sec\n",
values->stand.count, values->stand.zahl,
values->stand.count * values->stand.geldPerSecondIncrement);
printf(" 2 - Mines(%d)(%d$)\t\t\t\t+%d/sec\n",
values->mine.count, values->mine.zahl,
values->mine.count * values->mine.geldPerSecondIncrement);
printf(" 3 - Banks(%d)(%d$)\t\t\t\t+%d/sec\n",
values->bank.count, values->bank.zahl,
values->bank.count * values->bank.geldPerSecondIncrement);
printf(" 4 - Oil Refinerys(%d)(%d$)\t\t\t+%d/sec\n",
values->oil.count, values->oil.zahl,
values->oil.count * values->oil.geldPerSecondIncrement);
printf(" Q - Back to main menu\n");
printf("> ");
fflush(stdout);
return getCharacter();
}
void upgradeLoop(Values *values) {
char input = ' ';
while (input != 'Q' && g_keepGoing) {
input = getUpgradeInput(values);
switch (input) {
case '0':
upgrade(values, &values->werkzeug);
values->geldPerClick = 1 + values->werkzeug.count / 10;
break;
case '1':
upgrade(values, &values->stand);
break;
case '2':
upgrade(values, &values->mine);
break;
case '3':
upgrade(values, &values->bank);
break;
case '4':
upgrade(values, &values->oil);
break;
case 'Q':
break;
default:
break;
}
}
}
char getMainInput(Values *values) {
printHeader(values);
// make this easier to read in the code...
printf(" _ - [Space] get money\n");
printf(" U - Upgrades\n");
printf(" Q - Quit\n");
printf("> ");
fflush(stdout);
return getCharacter();
}
void mainLoop(Values *values) {
char input = ' ';
// while..do is easier to read and understand than do..while
while (input != 'Q' && g_keepGoing) {
// Encapsulate code in functions to make your program's logic
// easier to follow
input = getMainInput(values);
// Use a switch statement here and use character values
// rather than integers
switch (input) {
case ' ':
values->geld += values->geldPerClick;
clearLastMessage(values);
break;
case 'U':
upgradeLoop(values);
clearLastMessage(values);
case 'Q':
break;
default:
break;
}
};
}
void sigintHandler(int signal) {
printf("SIGINT received, cleaning up.\n");
restoreStdinTermios();
g_keepGoing = 0;
}
int main() {
Values values;
initializeValues(&values);
setNonBlockingBufferingStdinTermios();
signal(SIGINT, sigintHandler);
mainLoop(&values);
restoreStdinTermios();
return 0;
}
I'm using the LXLE 14.04 distribution of Linux.
I want to write a C program to read commands, interpret and perform them. I'd like the program to be efficient, and I do not want to use
a linked list.
The commands are operations on sets.
Each set can contain any of the values from 0 through 127 inclusive.
I decided to represent a set as an array of characters, containing 128 bits.
If bit at position pos is turned on then the number pos is in the set and if the bit at position pos is turned off then the number pos is
not present in the set. For example, if the bit at position 4 is 1, then the number 4 is present in the set, if the bit at position 11 is 1 then the number
11 is present in the set.
The program should read commands and interpret them in a certain way.
There are a few commands: read_set, print_set, union_set, intersect_set, sub_set and halt.
For example, the command read_set A,1,2,14,-1 in the terminal will cause the reading of values of the list into the specified set in the command.
In this case the specified set in the command is A. The end of the list is represented by -1. So after writing this command, the set A will contain the elements 1,2,14.
This is what I have so far.
Below is the file set.h
#include <stdio.h>
typedef struct
{
char array[16]; /*Takes 128 bits of storage*/
}set;
extern set A , B , C , D , E , F;
This is the file main.c
#include <stdio.h>
#include "set.h"
#include <string.h>
#include <stdlib.h>
set A , B , C , D , E , F; /*Variable definition*/
void read_set(set s,char command[])
{
int i, number = 0 , pos;
char* str_num = strtok(NULL,"A, ");
unsigned int flag = 1;
printf("I am in the function read_set right now\n");
while(str_num != NULL) /*without str_num != NULL get segmentation fault*/
{
number = atoi(str_num);
if(number == -1)
return;
printf("number%d ",number);
printf("str_num %c\n",*str_num);
i = number/8; /*Array index*/
pos = number%8; /*bit position*/
flag = flag << pos;
s.array[i] = s.array[i] | flag;
str_num = strtok(NULL, ", ");
if(s.array[i] & flag)
printf("Bit at position %d is turned on\n",pos);
else
printf("Bit at position %d is turned off\n",pos);
flag = 1;
}
}
void print_set(set s)
{
unsigned int flag = 1; int in_set = 0;
int i = 0;
while(s.array[i] != -1)
{
if(s.array[i] & flag)
{
in_set = s.array[i];
printf("%d,",in_set );
}
i++;
flag = 1;
}
}
int main()
{
#define CMD_LENGTH 256
char command[CMD_LENGTH]; char* letter;
printf("Please enter a command");
gets(command);
letter = strtok(command,"read_set ,");
switch(*letter)
{
case 'A':
{
read_set(A,command);
break;
}
case 'B':
{
read_set(B,command);
break;
}
case 'C':
{
read_set(C,command);
break;
}
case 'D':
{
read_set(D,command);
break;
}
case 'E':
{
read_set(E,command);
break;
}
case 'F':
{
read_set(F,command);
break;
}
}
return 0;
}
Clearly, it is not a good practice to write a bunch of switch statements and using strtok for each command, and repeating the code written in the main function for each command in order to call the different functions. I thought about using a pointer to a generic function, but since each function receives different parameters,
I do not think this is going to work.
Is there a better way of doing this?
Thanks in advance!
Update #1:
Here's the code. I've made some changes to it.
#include <stdio.h>
#include "set.h"
#include <string.h>
#include <stdlib.h>
set A , B , C , D , E , F; /*Variable definition*/
set sets[6];
/*Below I want to initialize sets so that set[0] = A set[1] = B etc*/
sets[0].array = A.array;
sets[1].array = B.array;
sets[2].array = C.array;
sets[3].array = D.array;
sets[4].array = E.array;
sets[5].array = F.array;
void read_set(set s,char all_command[])
{
int i, number = 0 , pos;
char* str_num = strtok(NULL,"A, ");
unsigned int flag = 1;
printf("I am in the function read_set right now\n");
while(str_num != NULL) /*without str_num != NULL get segmentation fault*/
{
number = atoi(str_num);
if(number == -1)
return;
printf("number%d ",number);
printf("str_num %c\n",*str_num);
i = number/8; /*Array index*/
pos = number%8; /*bit position*/
flag = flag << pos;
s.array[i] = s.array[i] | flag;
str_num = strtok(NULL, ", ");
if(s.array[i] & flag)
printf("Bit at position %d is turned on\n",pos);
else
printf("Bit at position %d is turned off\n",pos);
flag = 1;
}
}
typedef struct
{
char *command;
void (*func)(set,char*);
} entry;
entry chart[] = { {"read_set",&read_set} };
void (*getFunc(char *comm) ) (set,char*)
{
int i;
for(i=0; i<2; i++)
{
if( strcmp(chart[i].command,comm) == 0)
return chart[i].func;
}
return NULL;
}
int main()
{
#define PER_CMD 256
char all_comm[PER_CMD]; void (*ptr_one)(set,char*) = NULL; char* comm; char* letter;
while( (strcmp(all_comm,"halt") != 0 ) & (all_comm != NULL))
{
printf("Please enter a command");
gets(all_comm);
comm = strtok(all_comm,", ");
ptr_one = getFunc(comm);
letter = strtok(NULL,",");
ptr_one(A,all_comm);
all_comm[0] = '\0';
letter[0] = '\0';
}
return 0;
}
I get the following compile error:
main.c:9:8: error: expected ���=���, ���,���, ���;���, ���asm��� or ���attribute��� before ���.��� token
What's my mistake? How can I fix this?
Thanks a lot! #Claim Yang
However,in your case, using switch is almost the best solution to this.
Another way without switch is using a simple way to get an index. Here is a simple solution.
set sets[6];
read_set(sets[*letter - 'A'], command);
Then if you need to read a command, another array of pointers to functions is needed. Like below:
void (*functions[3])(set,char[]);
functions[0] = read_set;
And so on.
The point is coverting your string to an int, so it can be seen as an index of an array.
Then call functions like functions[string_to_int(string)](set,char[]);