#include<stdio.h>
int main() {
    int n, x, min = 100000;
    scanf("%d", &n);
    for (int i = 0; i < n; i++) {
        scanf(*"%d", &x);
        if (x < 0) {
            printf("Invalid Input");
            return 0;
        }
        if (x > 0 && x < min)
            min = x;
        
    }
    printf("&d", min);
    return 0;
}