How do we fill the elements of a 2d array

Question

#include <stdio.h>

#include <stdlib.h>

#define size 4

int main(void) 
{
    char a[size] [size];

    int i, j,u=0,n=0; 

    for(i=0;i<=size-1; i++)
    {
        for(j=0;j<=size-1;j++)
        {
            a[i] [j]= '*';

            printf(" %c",a[i] [j]); 


        }
        printf("\n");
    }
    printf("\n\n");

    srand(time(NULL)) ;

  for(;;)
  {  
    printf("enter some thing\n");

    a[rand()%size][rand()%size]=getchar(); 



    for(i=0;i<=size-1; i++)
    {
        if (u==size)

        break;

        for(j=0;j<=size-1;j++)
        { 
        if (a[i] [j] =='\0')

         a[i] [j] ='*';

            printf(" %c",a[i] [j]);     

        }
        printf("\n");
    u++;
    }
    n++;

    if (n==2)
    {
        u=0;

        n=0;
    }

    printf("\n\n");

}



    return 0;
}

The problem that I'm having with this code is that; the array loses it content as it's being filled leaving out blank spaces.and further more it arrangement changes.. I don't know why my program or compiler behave like this I don't even know where is the problem from. Worse is that this behavior is unpredictable. Below is a screen shoot of what I'm trying to say

This screenshot is realized with my phone but actually I'm using Ubuntu gcc compiler.

I will like that some one tells me why it is behaving like that and also to get some solutions to over come this problem.

Thanks for answering.

This is a common FAQ, you need to get rid of the newline character introduced to stdin each time you press enter. — Lundin, Sep 25 '17 at 15:12
Aside please do not use `i<=size-1;` it is harder to read than `i — Weather Vane, Sep 25 '17 at 15:14
The problem is not at using for(;;) or I<=size-1..I rectified them, still the same thing is given out — giles, Sep 25 '17 at 15:19

How do we fill the elements of a 2d array

0 Answers0