Thread: EOF in a while loop for arrays

With so many syntax errors, who can say.

Missing ; and & all over the place.

I suggest a comparing with 1 rather than EOF, since you expect one assignment from scanf on each iteration:

Code:

int i = 0;
int del[10000];

while (scanf("%d", &del[i]) == 1)
{
    i++;
}

Next, how do you know that i is not incrementing? Did you print it out? What is the input that you provided for the testing? Did you redirect it from a file, or did you trigger EOF (e.g., with CTRL + Z or CTRL + D)?

I tested with this program:

Code:

#include <stdio.h>

int main(void)
{
    int i = 0;
    int j;
    int del[10000];
     
    while (i < 10000 && scanf("%d", &del[i]) == 1)
    {
        i++;
    }

    printf("These are the entries:\n");
    for (j = 0; j < i; ++j)
    {
        printf("%d\n", del[j]);
    }
    printf("Total of %d entries.\n", i);

    return 0;
}

Entering this input followed by triggering EOF:

Code:

1 2 3 4 5 6 7

I received this output:

Code:

These are the entries:
1
2
3
4
5
6
7
Total of 7 entries.

EDIT:

Originally Posted by Snowflake

if I use your code is EOF going to be active?

EOF means "end of file". If the end of file has been reached, then there will not be any more input from that input stream, so when you attempt to read with scanf, you will get EOF (the value, not the condition) returned. EOF != 1, so the loop will end. While you could compare with EOF instead of 1, with more complex format strings that might be undesirable, or it might even be possible for scanf to return 0.