---

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

#include "../data_libs/data_io.h"
#include "decision.h"

int main(void) {
    double *data = NULL;
    int n;

    if (scanf("%d", &n) != 1 || n <= 0) {
        printf("n/a");
    } else {
        data = malloc(n * sizeof(double));

        if (data == NULL || !input(data, n)) {
            printf("n/a");
        } else if (make_decision(data, n)) {
            printf("YES");
        } else {
            printf("NO");
        }
    }

    free(data);

    return 0;
}