题解 | #树查找#

#include <stdio.h>
#include <math.h>
int main() {
    int n;
    while (scanf("%d", &n) != EOF) {
        int a[n];
        for (int i = 0; i < n; i++) {
            scanf("%d", &a[i]);
        }
        int m;
        scanf("%d", &m);
        int low = pow(2, m - 1) - 1;
        int high = pow(2, m) - 2;
        if (low > n - 1) {
            printf("EMPTY\n");
        } else{
            for (int i = low; (i < high) && (i < n); i++) {
                printf("%d ", a[i]);
            }
            printf("%d\n", a[high]);
        }

    }
    return 0;
}