#include <stdio.h>
#include <stdlib.h>

int main() {
    FILE *fp1, *fp2;
    int c1, c2, pos = 1;

    if((fp1 = fopen("output3.txt", "r")) == NULL){
        fprintf(stderr, "Failed to open: output3.txt\n");
        exit(1);
    }
    if((fp2 = fopen("output3_sample.txt", "r")) == NULL){
        fprintf(stderr, "Failed to open: output3_sample.txt\n");
        fclose(fp1);
        exit(2);
    }
    while(1){
        c1 = fgetc(fp1);
        c2 = fgetc(fp2);
        if(c1 != c2){
            printf("Two files are different at %d byte.\n", pos);
            break;
        }
        if(c1 == EOF){
            printf("Two files are identical.\n");
            break;
        }
        pos++;
    }
    fclose(fp1);
    fclose(fp2);
    return 0;
}