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


int contains_lowercase(char *path);

int main(int argc, char *argv[]) {
    if (argc <= 1) {
        fprintf(stderr, "Usage: %s <filename>\n", argv[0]);
        return 1;
    }
    int result = contains_lowercase(argv[1]);
    if (result != -1) {
        printf("Contains %c\n", result);
    } else {
        printf("Does not contain lowercase\n");
    }

    return 0;
}

// Check whether the given file contains a byte that could represent lowercase ascii 
// Return the first lowercase byte found.
// Return -1 otherwise
int contains_lowercase(char *path) {
    FILE *f = fopen(path, "r");
    if (f == NULL) {
        perror("");
        return -1;
    }

    int curr_byte;
    while ((curr_byte = fgetc(f)) != EOF){
        if (curr_byte >= 'a' && curr_byte <= 'z') {
            fclose(f);
            return curr_byte;
        }
    }

    fclose(f);
    return -1;
}