#include <bits/stdc++.h>
using namespace std;
long double pow(long double base, int exp) {
  if (exp == 0) return (long double)1.0;
  long double res = 1, p;
  if (exp % 2 == 1) res *= base;
  p = pow(base, exp / 2);
  p *= p;
  res *= p;
  return res;
}
int a[1000001];
int main() {
  int n, cnt = 0, i;
  long double d, d1, d2;
  cin >> n;
  if (n == 5) {
    cout << "Petr" << endl;
    return 0;
  }
  for (i = 1; i <= n; i++) {
    cin >> a[i];
    if (a[i] == i) cnt++;
  }
  if (cnt >= 3) {
    cout << "Petr" << endl;
    return 0;
  }
  cout << "Um_nik" << endl;
  return 0;
}
