Implement Custom strcmp function

Code

#include <stdio.h>
#include <string.h>

int custom_strcmp(const char *a, const char *b) {
    int i = 0;
    while (a[i] && b[i]) {
        if (a[i] != b[i]) {
            return a[i] - b[i];
        }
        i++;
    }
    return a[i] - b[i];
}

int main() {
    char a[101], b[101];

    fgets(a, sizeof(a), stdin);
    fgets(b, sizeof(b), stdin);

    // Remove newline
    a[strcspn(a, "\n")] = '\0';
    b[strcspn(b, "\n")] = '\0';

    printf("%d", custom_strcmp(a, b));

    return 0;
}

Solving Approach