#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include <dirent.h>

#define MAX_DEPTH 4

void print_regular_files(const char* dir_path, int depth, off_t max_size) {
    DIR* dir = opendir(dir_path);
    if (dir == NULL) {
        return;
    }

    struct dirent* entry;
    while ((entry = readdir(dir)) != NULL) {
        if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0) {
            continue;
        }

        char path[PATH_MAX];
        snprintf(path, sizeof(path), "%s/%s", dir_path, entry->d_name);

        struct stat st;
        if (lstat(path, &st) == -1) {
            continue;
        }

        if (S_ISREG(st.st_mode) && access(path, R_OK) != -1 && st.st_size <= max_size) {
            printf("%s\n", entry->d_name);
        } else if (S_ISDIR(st.st_mode) && depth < MAX_DEPTH) {
            print_regular_files(path, depth + 1, max_size);
        }
    }

    closedir(dir);
}

int main(int argc, char* argv[]) {
    if (argc < 3) {
        printf("Usage: ./yourprog directory max_size\n");
        return 0;
    }

    const char* dir_path = argv[1];
    off_t max_size = atoll(argv[2]);

    print_regular_files(dir_path, 0, max_size);

    return 0;
}