If I have those functions:
void main(void)
{
char *menu[] = {"data", "coming", "here"};
prints(**************); // here
printf("\n");
}
void prints(char **menu)
{
int a;
while(*menu)
{
printf("%s", **menu);
menu ++;
}
a = 0;
}
How to call prints function ???
Here is a version with several issues fixed:
#include <stdio.h>
// declare function before using it
void prints(char **menu)
{
// make sure parameter is valid
if (menu != NULL)
{
while(*menu)
{
// spaces so they don't run together
// pass *menu not **menu to printf
printf("%s ", *menu);
menu ++;
}
}
}
// proper return type for main()
int main(void)
{
// array terminator added
char *menu[] = {"data", "coming", "here", NULL};
prints(menu); // here
printf("\n");
// return with no error
return 0;
}
In C you must declare your function before another function that uses it. So...
void prints(char **menu)
{
int a;
while(*menu)
{
printf("%s", **menu);
menu ++;
}
a = 0;
}
void main(void)
{
char *menu[] = {"data", "coming", "here"};
prints(**************); // here
printf("\n");
}
That, or you can forward declare the function:
void prints(char **menu);
void main(void)
{
char *menu[] = {"data", "coming", "here"};
prints(**************); // here
printf("\n");
}
void prints(char **menu)
{
int a;
while(*menu)
{
printf("%s", **menu);
menu ++;
}
a = 0;
}
You can either move the prints function above main, or you can put a prototype for prints above main, like so:
void prints(char **menu);
Then, you can call prints from main just like any other function...
Related
This is a plane game function I wrote. I use a two-dimensional array to represent the game variables but The running result is abnormal, and * will jump suddenly.
And there will be two * , at the same time, and the plane also will stop
There should be no two * in the process of traversing the two-dimensional array. I tried to modify the position of * but I still couldn't.It's OK to run part of the code alone, but when you use the key operation, the program makes an error, but I don't know what's wrong
#include<stdio.h>
#include <windows.h>
#include<stdlib.h>
#include<conio.h>
#define enemynum 3
int element [20][30];
int position_x,position_y;
int enemy_x[enemynum],enemy_y[enemynum];
int score;
void gotoxy(int x, int y)
{
HANDLE handle = GetStdHandle(STD_OUTPUT_HANDLE);
COORD pos;
pos.X = x;
pos.Y = y;
SetConsoleCursorPosition(handle, pos);
}
void HideCursor()
{
CONSOLE_CURSOR_INFO cursor_info = {1,0};
SetConsoleCursorInfo(GetStdHandle(STD_OUTPUT_HANDLE), &cursor_info);
}
void startup()
{ element[20][30]={0};
position_x=10;position_y=15;
element[position_x][position_y]=1;
for(int k=0;k<enemynum;k++)
{
enemy_x[k]=rand()%3;enemy_y[k]=rand()%20;
element[enemy_x[k]][enemy_y[k]]=3;
}
HideCursor();
}
This is an encapsulated pointer callback function. I don't think we need to consider the above functions
void show()
{ int i,j;
gotoxy(0,0);
for(i=0;i<20;i++)
{
for(j=0;j<30;j++)
{ if(element[i][j]==1)
{
printf("*");
}else if(element[i][j]==3)
{
printf("#");
}
else
printf(" ");
}
printf("\n");
}
}
void updatewhithout()
{
int i,j;
for(i=0;i<20;i++)
{
for(j=0;j<30;j++)
{
if(element[i][j]==2)
{
element[i][j]=0;
if(i>0)
element[i-1][j]=2;
}
}
} static int flag;
if(flag<20)
flag++;
if(flag==20)
{ for(int k=0;k<enemynum;k++)
{
if(enemy_x[k]==20)
{
enemy_x[k]=rand()%3;
enemy_y[k]=rand()%20;
}
element[enemy_x[k]][enemy_y[k]]=0;
enemy_x[k]++;
element[enemy_x[k]][enemy_y[k]]=3;
flag=0;
}
}
}
void updatewhith()
{ char ch;
if( kbhit())
ch=getch();
if(ch=='a')
{ element[position_x][position_y]=0;
position_y--;
element[position_x][position_y]=1;
}
if(ch=='d')
{ element[position_x][position_y]=0;
position_y++;
element[position_x][position_y]=1;
}
}
int main()
{startup();
while(1)
{show();
updatewhithout();
updatewhith();
}
}
So the code below can be used to pass a function as a parameter:
void printNumber(int nbr)
{
printf("%d\n", nbr);
}
void myFunction(void (*f)(int))
{
for(int i = 0; i < 5; i++)
{
(*f)(i);
}
}
int main(void)
{
myFunction(printNumber);
return (0);
}
But how can I change that code so that the integer for “printNumber” is defined outside of “myFunction”? In other words I only want to call the function “myFunction” for x number of times with the same integer .
I wrote some pseudocode to explain what I'm trying to accomplish:
void printNumber(int nbr)
{
printf("%d\n", nbr);
}
void myFunction(void (*f)(*int)) //pseudocode
{
for(int i = 0; i < 5; i++)
{
(*f)(*int); //pseudocode
}
}
int main(void)
{
myFunction(printNumber(5)); //pseudocode
return (0);
}
printnumber(5) means to call printnumber immediately and pass it 5. You want to pass printnumber and 5 separately as two arguments
void printNumber(int nbr)
{
printf("%d\n", nbr);
}
// void (*f)(int) is a pointer to a function that takes an int
// arg is the int to pass in
void myFunction(void (*f)(int), int arg)
{
for(int i = 0; i < 5; i++)
{
// call f and pass in arg
(*f)(arg);
}
}
int main(void)
{
// pass the function and the arg to use
myFunction(printNumber, 5);
return (0);
}
You need another argument.
void printNumber(int nbr)
{
printf("%d\n", nbr);
}
void myFunction(void (*f)(int), int Arg)
{
for(int i = 0; i < 5; i++)
{
(*f)(Arg);
}
}
int main(void)
{
myFunction(printNumber, 42);
return (0);
}
The parameter declaration void (*f)(int) only says that the function pointed to by f expects an int. It doesn't mean that an int is also packed into the function pointer somehow.
I was practising some data structures problems that I did previously but this time I don't know what is going wrong in my code. I looked over a long time but I did not found the mistake. When I'm printing I'm just getting the first character and it looks like e is not being updated. But I've written e++.
#include<stdio.h>
#include "ctype.h"
int stack[20];
int top = -1;
void push(int x)
{
stack[++top] = x;
}
int pop()
{
return stack[top--];
}
int priorityof(char x)
{
if(x=='(')
return 3;
else if(x=='+'|| x=='-')
return 1;
else if(x=='*'|| x=='/')
return 2;
}
int main()
{
char exp[20];
char *e;
e=exp;char x;
scanf("%c",exp);
while(*e!='\0')
{
if(isalnum(*e))
{
printf("%c", *e);
}
else if(*e=='(')
{
push(*e);
}
else if(*e==')')
{
while((x=pop())!='(')
printf("%c",x);
}
else {
while (priorityof(stack[top]) >= priorityof(*e)) {
printf("%c", pop());
push(*e);
}
}
e++;
}
while(top!=-1)
{
printf("%c",pop());
}
}
%c is for single character and reading your question it seems like you are giving more than one character so its a string, use %s.
#include<stdio.h>
#include "ctype.h"
int stack[20]; int top = -1;
void push(int x) {
stack[++top] = x;
}
int pop() { return stack[top--]; }
int priorityof(char x) {
if(x=='(') return 3;
else if(x=='+'|| x=='-') return 1;
else if(x=='*'|| x=='/') return 2;
}
int main() {
char exp[20];
char *e;
e=exp;char x;
scanf("%s",exp);
while(*e!='\0') { if(isalnum(*e)) { printf("%c", *e); } else if(*e=='(') { push(*e); } else if(*e==')') { while((x=pop())!='(') printf("%c",x); } else { while (priorityof(stack[top]) >= priorityof(*e)) { printf("%c", pop()); push(*e); } } e++; } while(top!=-1) { printf("%c",pop()); } }
When I run my program, it will print "Welcome to Blackjack! Rules: " and then an error window will come up saying "Blackjack.exe has stopped working and I have to close the program. In the compiler window it says "Process terminated". How do I stop this from happening?
Is one of the loops not working correctly?
My code:
#include <stdio.h>
#include <stdlib.h>
void Initializedeck(int[]);
void Shuffledeck(int[]);
void displayscore(int, int);
int hdrawcards(int[], int[]);
char getsuit(int);
int cdrawcards(int[], int[]);
int main()
{
int deck[52];
char cont;
int hcherries=10;
int ccherries=10;
int hcards[10];
int ccards[10];
int htotal;
int ctotal;
printf("Welcome to Blackjack!\n");
printf("Rules: \n ");
Initializedeck(deck);
cont='y';
while(cont=='y')
{
Shuffledeck(deck);
system("cls");
displayscore(hcherries, ccherries);
htotal=hdrawcards(hcards, deck);
ctotal=cdrawcards(ccards, deck);
if(htotal>ctotal)
{
printf("You Win!");
}
else
{
printf("Computer Wins. :( ");
}
printf("Do you want to continue?(y/n)");
scanf("%c", &cont);
}
return 0;
}
void Initializedeck(int deck[])
{
int i=0;
while(i<52)
{
deck[i]=i;
i++;
}
}
void Shuffledeck(int deck[])
{
int hold;
int max=51;
int random;
while(max>=0)
{
random=rand()%(max)+1;
hold=deck[max];
deck[max]=random;
random=hold;
max--;
}
}
void displayscore(int hcherries, int ccherries)
{
printf("Human: %i(cherries) Computer: %i(cherries)", hcherries, ccherries);
}
int hdrawcards(int hcards[], int deck[])
{
char answer;
int i=0;
int score=0;
int total=0;
char rank;
int worth;
char suit;
int card;
printf("Do you want to draw a card? (y/n)");
scanf("%c", &answer);
while(answer=='y' && total<21)
{
score=score+deck[i];
hcards[i]=deck[i];
card=hcards[i];
worth=hcards[i]%13;
if(worth==10)
{
rank='T';
}
else if (worth==11)
{
rank='J';
}
else if (worth==12)
{
rank='Q';
}
else if (worth==13)
{
rank='K';
}
else if(worth==1)
{
rank='A';
}
else
{
rank=worth;
}
if(worth>10)
{
worth=10;
}
total=total+worth;
suit=getsuit(card);
printf("%c%c\n", rank, suit);
printf("Total: %i", total);
i++;
scanf("%c", &answer);
}
return total;
}
int cdrawcards(int ccards[], int deck[])
{
int i=26;
int total;
int score;
int worth;
char rank;
char suit;
int card;
while(total<18)
{
score=score+deck[i];
ccards[i]=deck[i];
card=ccards[i];
worth=ccards[i]%13;
if(worth==10)
{
rank='T';
}
else if (worth==11)
{
rank='J';
}
else if (worth==12)
{
rank='Q';
}
else if (worth==13)
{
rank='K';
}
else if(worth==1)
{
rank='A';
}
else
{
rank=worth;
}
if(worth>10)
{
worth=10;
}
total=total+worth;
suit=getsuit(card);
printf(" %c%c\n", rank, suit);
printf(" Total: %i", total);
i++;
}
return total;
}
char getsuit(int card)
{
char suit;
if(card<13)
{
suit='S';
}
else if(card>=13 && card<26)
{
suit='H';
}
else if(card>=26 && card<39)
{
suit='D';
}
else if(card>=39 && card<52)
{
suit='C';
}
return suit;
}
You have an array overflow in cdrawcards():
int ccards[10];
...
ctotal = cdrawcards(ccards, deck);
...
int cdrawcards(int ccards[], int deck[])
{
int i = 26;
...
ccards[i] = deck[i]; //Overflow, ccards[] only has 10 elements
Either change the initial value of i or make the array larger int ccards[52]. I would also add an explicit check in cdrawcards() and hdrawcards() to ensure you don't overflow the arrays, like:
while (total < 18 && i < 10)
For example, in hdrawcards() you can overflow the array if you get a bunch of low value cards in a row (ex: 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3(overflow), 3, ...).
I want to remove element from b->array as shown in below code:removeItem function
I have tried to remove 12.12 from the b->array = {11.11,12.12,13.13}but it leads to segmentation fault instead of printing {11.11,13.13}. can anybody help to get rid of it?
typedef struct
{
float val;
}data;
typedef struct
{
data **array;
int size;
}bag;
int main(int argc,char* argv[])
{
bag *str = createBag();
#ifdef DEBUG
printf("Inital values: %p %d\n",str->array,str->size);
#endif
data *iptr = createData(10.10);
data *iptr1 = createData(11.11);
data *iptr2 = createData(12.12);
data *iptr3 = createData(13.13);
data *iptr4 = createData(14.14);
#ifdef DEBUG
printf("%f\n",iptr->val);
#endif
addData(str,iptr);
addData(str,iptr1);
addData(str,iptr2);
addData(str,iptr3);
addData(str,iptr4);
printBag(str);
data *ptr = getData(str,4);
printf("Data item 4 is:%f\n",ptr->val);
int b = getBagSize(str);
printf("Size of bag: %d\n",b);
removeBack(str);
printBag(str);
removeFront(str);
printBag(str);
//cleanBag(str);
int s = searchBag(str,10.10);
printf("%d\n",s);
removeItem(str,12.12);
printBag(str);
return 0;
}
bag* createBag()
{
bag *str = (bag*)malloc(sizeof(bag));
str->array = NULL;
str->size = 0;
return str;
}
data* createData(float v)
{
data *iptr = (data*)malloc(sizeof(data));
iptr->val = v;
return iptr;
}
void addData(bag* b, data* d)
{
b->size++;
data** array1 = (data**)malloc(sizeof(data*)* b->size);
if(b->array!= NULL)
{
int i;
for(i = 0; i<b->size;i++)
{
array1[i] = b->array[i];
}
}
free(b->array);
array1[b->size-1] = d;
b->array = array1;
}
void printBag(bag *b)
{
int i;
for(i=0; i<b->size;i++)
{
printf("%f\n",b->array[i]->val);
}
}
data* getData(bag *b, int pos)
{
if(pos>5)
{
printf("change array position\n");
}
return b->array[pos];
}
int getBagSize(bag *b)
{
return b->size;
}
void removeBack(bag *b)
{
b->size--;
free(b->array[b->size]);
data **array2 = (data**)malloc(sizeof(data*)* b->size);
if(b->array!= NULL)
{
int i;
for(i = 0; i<b->size;i++)
{
array2[i] = b->array[i];
#ifdef DEBUG
printf("%f\n",array2[i]->val);
#endif
}
free(b->array);
b->array = array2;
}
}
void removeFront(bag *b)
{
b->size--;
free(b->array[0]);
data **array2 = (data**)malloc(sizeof(data*)* b->size);
if(b->array!= NULL)
{
int i;
for(i = 0; i<b->size;i++)
{
array2[i] = b->array[i+1];
#ifdef DEBUG
printf("%f\n",array2[i]->val);
#endif
}
free(b->array);
b->array = array2;
}
}
/*void cleanBag(bag *b)
{
int i;
for(i=0;i<b->size;i++)
{
free(b->array[i]);
}
free(b->array);
free(b);
}*/
int searchBag(bag *b,float v)
{
int i;
for(i=0;i<b->size;i++)
{
if(b->array[i]->val==v)
{
return (i+1);
}
}
return -1;
}
void removeItem(bag *b, float v)
{
int flag = 0,i = 0;
flag = searchBag(b,v);
if(flag != -1)
{
data **array2 = (data**)malloc(sizeof(data*)*(b->size-1));
for(i = 0; i < (b->size); i++)
{
if(i == (flag-1))
{
i = i + 1;
continue;
}
array2[i] = b->array[i];
}
free(b->array);
b->size--;
b->array = array2;
}
else
{
printf("Element is not found\n");
}
}
There are two mistakes in your code.
searchBag returns 0, if the float value is not found in the bag.
However, the function removeItem test for if(flag != -1). It should test for if(flag != 0) instead.
The reason for the seg. fault you encountered also lies in the removeItem function.
Note how the memory allocated for array2 is for b->size-1 elements only. Valid array indices for this array are in the range of 0 ... b->size-2.
Now, look at the for loop, and you will note that the index variable i will run from 0 to b->size-1. Exactly in the last iteration i will become b->size-1, so the code tries to write at the location array2[b->size-1] which is beyond the allocated memory of array2.
A possible fix of the removeItem function could look like this:
void removeItem(bag *b, float v)
{
int flag = 0;
int oldArrayIndex = 0;
int newArrayIndex = 0;
flag = searchBag(b,v);
if(flag != 0)
{
data **array2 = (data**) malloc(sizeof(data*)*(b->size-1));
for(oldArrayIndex = 0; oldArrayIndex < (b->size); oldArrayIndex++)
{
if(oldArrayIndex != (flag-1))
{
array2[newArrayIndex] = b->array[oldArrayIndex];
newArrayIndex++;
}
}
free(b->array);
b->size--;
b->array = array2;
}
else
{
printf("Element is not found\n");
}
}