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

int main(int argc, char **argv) {
    if (argc < 2) {
        fprintf(stderr, "usage: %s <megabytes>\n", argv[0]);
        return 1;
    }
    long mb = strtol(argv[1], NULL, 10);
    if (mb <= 0) return 1;

    size_t bytes = (size_t)mb * 1024 * 1024;
    char *p = (char *)malloc(bytes);
    if (!p) {
        fprintf(stderr, "malloc failed\n");
        return 2;
    }
    for (size_t i = 0; i < bytes; i += 4096) {
        p[i] = (char)(i & 0xff);
    }
    volatile char sink = p[bytes - 1];
    (void)sink;

    printf("ok %ld\n", mb);
    return 0;
}