Can't find the problem with my number guessing game. (C) - c

I have managed to create a game that tries to guess what the user is thinking about, but the problem is that the number guessed is stored into l_guess or h_guess depending on the condition met, how can I store it into a third variable that would be the new guess used on the next guess?
My question might not be clear, but I hope looking at the code will help.
// Assignment #7
// This program guesses the number that you have picked.
#include <stdio.h>
#define UPPER 100
#define first_Guess 50
char answer;
int h_Guess;
int l_Guess;
int new_Guess;
void game_Start();
void game_Play();
int main(void)
{
h_Guess = (first_Guess + UPPER) / 2;
l_Guess = first_Guess;
game_Start();
game_Play();
return 0;
}
void game_Start()
{
printf("Hello, and welcome to the guessing game\n Think of a number between 0 and 100 and I will try to guess it.\n");
printf("... Is it %d ?", first_Guess);
printf("If the answer is correct, press (c) \n If your number is higher, press (h)\n if your number is lower, press (l)\n");
scanf("%c", &answer);
}
void game_Play()
{
while (answer != 'c')
{
if (answer == 'h')
{
printf("Then ... is it %d?\n", h_Guess);
h_Guess = (h_Guess + UPPER) / 2;
}
else if (answer == 'l')
{
l_Guess = l_Guess / 2;
printf("Then ... is it %d?\n", l_Guess);
}
scanf("%c", &answer);
}
printf(" I knew it, I am a genius\n");
}

You're not properly re-setting the boundaries of your guesses.
void game_Play()
{
int upper = MAX;
int lower = MIN;
int guess = FIRST_GUESS;
while (answer != 'c')
{
if (answer == 'h')
{
lower = guess;
}
else if (answer == 'l')
{
upper = guess;
}
guess = (upper + lower) / 2;
printf("Then is it %d?\n", guess);
scanf(" %c", &answer);
}
printf(" I knew it. I am a genius.\n");
}
Note: with your constants defined as they are, there is an edge-case error in my solution. Can you find it, and fix it?

Related

C code stops after if statement inside while loop

I am trying to create a program that assigns the user one of three questions at random. I figured out that part however I want to make it so that after they correctly answer their assigned question that they are asked if they want to take another one.
int main(void) {
srand(time(0));
int luckyNumber;
int quizNumber;
int score;
int totalScore;
int averageScore;
int attempts;
char answer1;
char answer2;
char answer3;
char opt1;
char loop = 'y';
printf("Welcome to the quiz program!\n");
while(loop == 'y') {
printf("Please enter a lucky number between 1 and 9: ");
scanf("%d", &luckyNumber);
quizNumber = rand() % 3 + 1;
printf("Your quiz number is %d\n", quizNumber);
if (quizNumber == quizNumber) {
while (score != 5) {
printf("Quiz 1\n");
printf("A. True\n");
printf("B. False\n");
printf("Enter your answer: ");
scanf(" %c", &answer1);
if (answer1 == 'B' || answer1 == 'b') {
printf("Correct!\n");
score = score + 5;
break;
}
else {
printf("Incorrect!, Try again.\n");
printf("\n");
}
break;
}
break;
}
printf("Would you like to go again y/n?");
scanf("%c", &loop);
if (loop != 'y')
loop = 'n';
}
return 0;
}
The problem I am having is after I compile the code, it stops when the correct answer is input rather than going on to ask if the user would like to do another quiz.

Is my do while loop not working due to this function?

Im making a program where it asks the user to guess a number 1-100 that the computer is thinking about.
In the end of the program, when the user has guessed the correct number, im trying to get the program to ask if user wants to play again (restart the program).
To solve this, i tried using a do while loop & char repeat;. The loop is stretching from almost the beginning of the program, until the end, althought without success. Does anyone know what im doing wrong? Is it because of the function talfunktion, that the loop won't pass?
Code:
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int talfunktion (int tal, int guess, int tries, char repeat);
int main () {
do {
srand(time(NULL));
int tal = rand() % 100 + 1; //tal is the correct value that the code is thinking of
int guess; //guess is the guessed value of the user
int tries = 0; // amount of tries it took until getting correct
char repeat;
printf("Psst, the right number is: %d \n", tal); // remove later, not relevant to uppg.
printf("Im thinking of a number between 1 and 100, guess which!");
printf("\nEnter: ");
scanf("%d", &guess);
guess = talfunktion(tal, guess, tries, repeat);
getchar();
getchar();
return 0;
}
int talfunktion(int tal, int guess, int tries, char repeat) {
do {
if (guess < tal) {
tries++;
printf("\nYour guess is too low, try again!");
printf("\nEnter: ");
scanf("%d", &guess);
}
else if (guess > tal) {
tries++;
printf("\nYour guess is too high, try again!");
printf("\nEnter: ");
scanf("%d", &guess);
}
} while (guess > tal || guess < tal);
if (guess == tal) {
printf("\nCongratulations, that is correct!");
tries++;
printf("\nYou made %d attempt(s)", tries);
printf("\nPlay Again? (y/n)");
scanf("%c", &repeat);
}
} while (repeat == 'y' || repeat == 'Y');
}
This is one possible solution
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
void talfunktion(int tal, int guess, int* tries)
{
if (guess < tal)
{
(*tries)++;
printf("\nYour guess is too low, try again!");
}
else if (guess > tal)
{
(*tries)++;
printf("\nYour guess is too high, try again!");
}
else if (guess == tal)
{
(*tries)++;
printf("\nCongratulations, that is correct!");
printf("\nYou made %d attempt(s)", *tries);
}
}
int main (void)
{
int tal; //tal is the correct value that the code is thinking of
int guess; //guess is the guessed value of the user
int tries = 0; // amount of tries it took until getting correct
char playAgain;
do {
srand(time(NULL));
tal = rand() % 100 + 1; //tal is the correct value that the code is thinking of
printf("\nIm thinking of a number between 1 and 100, guess which!");
printf("\nEnter: ");
scanf("%d", &guess);
talfunktion(tal, guess, &tries);
printf("\nPsst, the right number is: %d", tal); // remove later, not relevant to uppg.
getchar(); //to halt the code for taking the input
if(guess == tal)
{
tries = 0;
printf("\nPlay Again? (y/n)\n");
scanf("%c", &playAgain);
}
} while (playAgain != 'n');
return 0;
}
There are several things mentioned in the comments that describe problems,
Things you should look at:
Do not define a function inside another function
be careful where you place return statements
when using character testing, use char type for variable
consider simplifying your logical comparisons. (eg guess > tal || guess < tal is the same as guess != tal )
make sure automatic variables are placed such that they are visible where used.
Place space in format specifier: " %c" for scanf() to consume newline character. (instead of excessive use of getchar())
Here is a simplified version of your code, with modified main and talfunktion functions...
char talfunktion(int tal);
int main (void) {
int tal=0;//remove from inside {...} to make it visible to rest of function
char repeat = 'n';
srand(time(NULL));
tal = rand() % 100 + 1; //tal is the correct value that the code is thinking of
do {
repeat = talfunktion(tal);
}while((tolower(repeat) == 'y'));
return 0;
}
char talfunktion(int tal)//do all relevant work in function and return
{ //only what is necessary
int guess = 0;
char repeat = 'n';
printf("Im thinking of a number between 1 and 100, guess which!");
printf("\nEnter a number from 1 to 100: ");
scanf("%d", &guess);
if((guess < 1) || (guess > 100))
{
printf("Entered out of bounds guess...\n");
}
else if (guess != tal)
{
if(guess < tal) printf("guess too small\n");
else printf("guess too large\n");
printf("Try again? <'n' or 'y'>\n");
scanf(" %c", &repeat);//space in format specifier to consume newline character
if(tolower(repeat) != 'y') return 'n';//tolower() allows both upper and lower case
}
else
{
printf("Congratulations: You guessed right.\n");
printf("Play again? <'n' or 'y'>\n");
scanf(" %c", &repeat);
}
return repeat;
}

Running into a segfault when referencing pointer

I'm taking an intro to C programming course, and I'm trying to understand pointers, and how exactly they work. I tried to pass just the variable counter through gameRuntime();, but counter wasn't being returned towards after the while loop. So, I opted to use a pointer. And now I'm in a bigger mess than I started.
Code:
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int *gameRuntime(int *counter)
{
srand(time(NULL));
int random = rand() % 100 + 1;
printf("> %d <\n", random);
int guess;
*counter = 1;
int local_counter = (*counter);
while ((guess != random) && (local_counter <= 10))
{
printf("\n-----------------------\n");
printf("What is your guess?\n-----------------------\n> ");
scanf("%d", &guess);
if ((guess > 100) || (guess < 1))
{
printf("Please choose a number between 1 and 100\n");
}
else if (guess < random)
{
printf("My number is larger than %d!\n", guess);
local_counter++;
printf("%d guesses left!\n", (11 - local_counter));
}
else if (guess > random)
{
printf("My number is less than %d!\n", guess);
local_counter++;
printf("%d guesses left!\n", (11 - local_counter));
}
else if (guess == random)
{
printf("You guessed it! My number was %d!\n", random);
printf("You found it with just %d guess(es)!\n", local_counter);
}
}
(*counter) = local_counter;
return counter;
}
int main()
{
char quit;
int counter;
int random;
printf("Welcome to the Number Guess Game!\n");
printf("I chose a number between 1 and 100 and you have only 10 chances to guess it!\n\n");
printf("Continue? [Y\\N]\n\n> ");
scanf("%c", &quit);
if ((quit == 'n') || (quit == 'N'))
{
printf("Exiting....");
return 0;
}
else
{
printf("\n=*=+=*=+=*=+=*==*=+=*=+=*=+=*==*=+=*=+=*=+=*==*=+=*=+=+*\n");
printf(" ~ ~ ~ Ready? ~ ~ ~ \n");
printf("=*=+=*=+=*=+=*=+=*=+=*=+=*=+=*=+=*=+=*=+=*=+=*=+=*=+=*=+=*\n");
printf("\n");
printf("\n-----------------------");
printf("\nOk, I've made up my mind!\n");
printf("-----------------------\n");
}
gameRuntime(counter);
printf("\n---%d---\n", counter);
char continueGame;
while ((continueGame != 'N') || (continueGame != 'n'))
{
printf("\n---%d---\n", counter);
if (counter >= 10)
{
printf("SORRY! You could not find my number with 10 guesses!\n");
printf("My number was %d\n", random);
printf("Maybe next time!\n");
printf("\nTry again? [Y\\N]\n");
scanf(" %c", &continueGame);
if ((continueGame == 'Y') || (continueGame == 'y'))
{
gameRuntime(counter);
}
else
{
printf("Thanks for playing! See you later!");
return 0;
}
}
else
{
printf("Play again? [Y\\N]\n> ");
scanf(" %c", &continueGame);
if ((continueGame == 'Y') || (continueGame == 'y'))
{
gameRuntime(counter);
}
else
{
printf("\nThanks for playing! See you later!");
return 0;
}
}
}
}
Any help would be much appreciated, TIA
Change
gameRuntime(counter);
to
gameRuntime(&counter);
You are passing the value of counter, and then you used it like if it was the address of something (you dereferenced the pointer). It does compile because pointers and ints are interchangeable in c, but that doesn't mean that the behavior is defined. It should however, generate a warning about pointer to int conversion. You can also, convert all warnings to errors to prevent compilation in case of a warning.
Warnings can be ignored in very rare cases, so as a rule of thumb make your compiler warn about everything it can and if possible, let it treat warnings as errors.
By applying the suggested fix, you pass the address of counter, which is a pointer holding the location of counter in memory, thus you can then affect the value at that location by dereferencing the pointer.

Is there any way to avoid using exit(0)?

I wanted to practice a little with separating logic into functions and using basic recursion in a primitive "Guess my number game", just as a sort of way to see where I'm at in my C programming.
Here's the code:
#include <stdio.h>
#include <time.h>
#include <stdlib.h>
#define TRUE 1
#define FALSE 0
char playAgain()
{
printf("\nDo you wanna play again? ");
char resp = 0;
while (TRUE) {
scanf("%c", &resp);
if (resp == 'y') break;
if (resp == 'n') break;
}
return resp;
}
void play()
{
srand((int)time(NULL));
int num = rand() % 10 + 1;
int guess = 0;
int flag = 0;
int attempts = 0;
printf("\nGuess the number: \n");
while (TRUE) {
scanf("%d", &guess);
if (num > guess)
{
printf("Too low! ");
attempts++;
}
else if (num < guess)
{
printf("Too high! ");
attempts++;
}
else if (num == guess)
{
attempts++;
printf("You won! You did it in %d attempts", attempts);
char yo = playAgain();
if (yo == 'y') play();
else if (yo == 'n') exit(0);
else {
printf("Error!");
exit(1);
}
}
}
}
int main()
{
return play();
}
Everything works but I've only managed to make it quit when the user says 'n', by using exit(0) and I've heard it's bad practice. But having spent a couple of hours just noodling around and trying all the other ways I could think of (using flags, for example), I just couldn't make it work. It works for 'y', but as soon as I enter 'n', it doesn't quit and just calls the playAgain() function one more time, or freezes altogether (nothing happens).
I feel ashamed for not being able to solve this, but I'm out of ideas. Is there any other way, other than exit(0), to make it jump out of play() straight to return 0 in main()? The problem seems to be that I have an infinite game loop, so when the answer is 'n', I need to break out of the loop AND out of the play() function, and that has proven to be problematic. I remember being able to do this easily when I had no functions, but just all the relevant code in main(), but the whole point of this is to use functions. For example, I can't figure out how to make use of a return type of play(), so that it knows when to quit.
P.S. As always, seeing how often people get accused of this, I assure you this is not homework because I am, and always have been, doing programming strictly as a hobby. There's no professor I answer to, apart from you :-) And trust me that I did try to figure out a solution, but nothing seems to work. It's a question of good vs. bad design, so it's especially important for my self-teaching. exit(0) seems to be a hackish solution and serves no educational purpose.
P.P.S. By the way, I'm using xCode, and the program runs in its output window. Probably not, but maybe that's the reason quitting with 'n' doesn't work?
SUMMARY: The code works fine except when the answer is 'n', in which case it just asks "Do you wanna play?" again, or doesn't do anything at all.
Make your play function return a result:- int play( void ) {
then instead of exit(1) and exit(0); use return 1; and return 0;
at the end of play put return 0;
then in main
{
return play();
}
instead of recursion, just make a loop
int play( void)
{
srand((int)time(NULL));
int num;
int guess;
int flag;
while(1)
{
num = rand() % 10 + 1;
guess = 0;
flag = 0;
printf("\nGuess the number %d: \n", num);
while (1) {
scanf("%d", &guess);
if (num > guess)
{
printf("Too low! ");
}
else if (num < guess)
{
printf("Too high! ");
}
else if (num == guess)
{
printf("You won!");
char yo = playAgain();
if (yo == 'y') break;
else if (yo == 'n') return 0;
else {
printf("Error!");
return 1;
}
}
}
}
}
and if you want more of a game engine type approach
enum {
GUESS,
GAMEOVER,
QUIT,
} GAME_STATES;
typedef struct
{
enum GAME_STATES state;
int num;
int game_over;
} guessing_game_t;
void init_game(guessing_game_t* g)
{
g->state = GUESS;
g->game_over = 0;
g->num = rand() % 10 + 1;
}
void evaluate_guess(guessing_game_t* g, int guess)
{
if(g->num == guess)
{
printf("You won!");
g->state = GAMEOVER;
}
else if (g->num > guess)
{
printf("Too low! ");
}
else if (g->num < guess)
{
printf("Too high! ");
}
}
int input_guess( void )
{
int guess;
scanf("%d", &guess);
return guess;
}
void play_again( guessing_game_t* g)
{
char resp = 0;
printf("\nDo you wanna play again? ");
scanf("%c", &resp);
if (resp == 'y') init_game(g);
if (resp == 'n') g->state = QUIT;
}
void play( guessing_game_t* g)
{
while(g->state != QUIT)
{
switch(g->state)
{
case GUESS:
evaluate_guess(g, input_guess());
break;
case GAMEOVER:
play_again(g);
break;
}
}
}
int main()
{
guessing_game_t game;
init_game(&game);
play(&game);
}
You can put a flag before going on with the loop
Change the while(true) to while (continue_play), continue_play is the name of flag for an example
Then,
if (yo == 'n') exit(0);
can be change to
if (yo == 'n') continue_play=false;
and do the similar for the exit(1) case
continue_play then will be a flag to exit from the function.
You have one more thing that the program will end: the logic of your code is made like that u can also use break; instead of exit(0) and exit(1) because you use while loop and you will break it and the program will end.
Since you may recursive call you play() function, I think exit it with exit(0) is a proper choose.
Acutall, I do not think using recursion to implement play() is a good idea at all, two infinite loops are enough. You could implemet it like this:
void play(void)
{
srand((int)time(NULL));
int num;
int guess = 0;
int attempts = 0;
int try_again = 1;
while (try_again) {
num = rand() % 10 + 1;
printf("\nGuess the number: \n");
while (TRUE) {
scanf("%d", &guess);
if (num > guess)
{
printf("Too low! ");
attempts++;
}
else if (num < guess)
{
printf("Too high! ");
attempts++;
}
else if (num == guess)
{
attempts++;
printf("You won! You did it in %d attempts", attempts);
char yo = playAgain();
if (yo == 'n') try_again = 0;
break;
}
}
}
}

Random number game C

The game works fine my first time through, although; the second time it only gives you two lives... I have tried to change the number of lives but still can't figure out what I'm doing wrong.
// C_program_random_number_game
#include<stdio.h>
#include<time.h>
#include <stdlib.h>
int main()
{
srand(time(NULL));
int num1,x = 0;
char game, cont, replay;
printf("Would you like to play a game? : ");
scanf("%c",&game);
if (game == 'y' || game == 'Y')
{
printf("\nThe rules are simple. You have have 5 tries to guess the computers number. \n \n If you succeed you win the game, if you dont you lose the game. Good luck!");
do
{
int r = rand()%5 +1;
printf("\n\nEnter a number between 1 and 5 : ");
scanf("\n%d",&num1);
x++;
if(num1 > 0 && num1 < 5)
{
do
{
if(num1 < r)
{
printf("\nClose! try a little higher... : ");
x++;
}
else if (num1 > r)
{
printf("\nClose! try a little lower...: ");
x++;
}
scanf("%d",&num1);
}while(num1!=r && x <3);
if(num1 == r)
{
printf("\nWinner! >> you entered %d and the computer generated %d! \n",num1, r);
}
else if(num1 != r)
{
printf("\nBetter luck next time!");
}
printf("\n\nWould you like to play again? (y or n) : ");
scanf("\n%c",&replay);
}
else
{
printf("Sorry! Try again : ");
scanf("%d",&num1);
}
}while(replay == 'y'|| replay == 'Y');
}
else if (game == 'n' || game == 'N')
{
printf("Okay, maybe next time! ");
}
else
{
printf("Sorry, invalid data! ");
}
return 0;
}
There are all kinds of issues with you code (most of them are minor in terms of programming). Most of the errors are typos in what you want done via this question and what you printf().
As is, this code will random between 1-25, accept an input of any valid int, see if you matched it, and only give you 5 tries. (I didn't add error checking to enforce that the input is between 1-25. That should probably be added.)
I commented my code below with all my changes and went by that you had in the printf()s.
Note: See my comments above for explanations of my changes since I already pointed them out. I also formatted it so its a little more easy to read.
Note2: I did this quickly using an online compiler. If you find anything wrong with this or not working as you'd like, just comment below and I'll address it.
// C_program_random_number_game
#include<stdio.h>
#include<time.h>
#include <stdlib.h>
int main()
{
srand(time(NULL));
int num1,x = 0;
char game, cont, replay;
printf("Would you like to play a game? : ");
scanf("%c",&game);
if (game == 'y' || game == 'Y')
{
printf("\nThe rules are simple. You have have 5 tries to guess the computers number. \n \n If you succeed you win the game, if you dont you lose the game. Good luck!");
do
{
int r = rand()%25 +1;
printf("\n\nEnter a number between 1 and 25 : ");
scanf("%d",&num1);
do
{
printf("r = %d\n", r);
if(num1 < r)
{
printf("\nClose! try a little higher... : ");
x++; //Increment x if wrong guess
}
else if (num1 > r)
{
printf("\nClose! try a little lower...: ");
x++; //Increment x if wrong guess
}
scanf("%d",&num1);
}while(num1!=r && x < 5); //If x is 5 or more, they ran out of guesses (also, you want an && not an ||)
if(num1 == r) //Only print "winner" if they won!
{
printf("\nWinner! >> you entered %d and the computer generated %d! \n",num1, r);
}
printf("\nWould you like to play again? (y or n) : ");
scanf("\n%c",&replay);
}while(replay == 'y'|| replay == 'Y');
}
printf("Thanks for playing! ");
if (game == 'n' || game == 'N')
{
printf("Okay, maybe next time! ");
}
return 0;
}
There are a combination of two problems. The first is that you're not breaking out of the "for" loop when the number matches. Therefore the match is only checked on every third guess.
The second problem is in this logic check:
}while(num1!=r || x <= 3);
We see that this turns into "true" if the for loop is broken out of early.

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