Displaying content of an array + taking input - arrays

Question

What in the world, is the matter here:
#include <stdio.h>
int main(int argc, char const *argv[])
{
int array[20];
int *pArray = array;
int count;
int i = 0;
while(1)
{
scanf("%d", array+i );
if(*(pArray+i) == -1) break;
i++;
}
printf("Contents: ");
while(1){
if (*(pArray + i) != -1)
{
printf("%d ", *(pArray + i) );
i++;
}
}
return 0;
}
Thank you. I am trying to take input from the user and then display the contents of the array. I was going to arrange them in order too using pointers, but I'll wait till someone replies.

Answer 1

Here is my rewrite attempt:
#include <stdio.h>
int main(void)
{
int array[20];
int i = 0;
while(1)
{
scanf("%d", &array[i] );
if(array[i] == -1) break;
i++;
}
printf("Contents: ");
i = 0; // RESET the counter back to ZERO.
while(1)
{
if (array[i] != -1)
{
printf("%d ", array[i] );
i++;
}
}
return 0;
}

Answer 2

You may be facing the error of stack around the variable array is corrupted. The reason is that you are first taking an input and then terminating the loop if the given input was -1.
scanf("%d", array+i );
if(*(pArray+i) == -1) break;
Now assume that i=20 what will happen???
Of course your code will crash on the scanf statement because it will try to access array+20 (the 20th index) which will not be allowed.
You also need to initialize the array first because when you declare an array, it contains junk values perhaps initializing the last index with zero will do the job. You can use the following code:
#include <stdio.h>
int main(void)
{
int array[20];
/*INITIALIZE THE LAST INDEX WITH -1 TO APPLY THE TERMINATING CONDITION*/
array[19] = -1;
int i = 0;
while(1)
{
scanf("%d", array+i );
i++; //INCREMENT HERE TO CHECK THE NEXT INDEX INSTEAD OF CHECKING THIS ONE
if(array+i == -1)
{
scanf("%d", array+i ); //TAKE THE INPUT FOR THE LAST INDEX
break; //TERMINATE THE LOOP
}
}
printf("Contents: ");
i = 0; // RESET the counter back to ZERO.
while(i != 20)
{
printf("%d ", array[i] );
i++;
}
return 0;
}
It seems like you are using pArray without any reason. array can also do exactly what you are trying to do with pArray. For arranging the order, you have to apply any sorting algorithm. Hope this helps.