10490.cpp

#include <bits/stdc++.h>

int prime(long long n) {
    long long i;
    if (i == 1) return 0;
    if (n == 2) return 1;
    if (n % 2 == 0) return 0;
    for (i = 2; i * i <= n; i++) {
        if (n % i == 0) return 0;
    }
    return 1;
}

int main() {
    long long p;
    int n;
    while (scanf("%d", &n)) {
        if (n == 0) return 0;

        p = pow(2, n) - 1;
        if (prime(p) == 1) {
            p *= pow(2, n - 1);
            printf("Perfect: %lld!\n", p);
        } else {
            if (prime(n) == 1) {
                printf("Given number is prime. But, NO perfect number is available.\n");
            } else {
                printf("Given number is NOT prime! NO perfect number is available.\n");
            }
        }
    }
    return 0;
}