#include <bits/stdc++.h>
using namespace std;
long long n, i, a[1000005], cnt;
int main() {
  cin >> n;
  for (i = 1; i <= n; i++) cin >> a[i];
  for (i = 1; i <= n; i++)
    while (a[i] != i) swap(a[i], a[a[i]]), cnt++;
  cout << (n % 2 == cnt % 2 ? "Petr" : "Um_nik");
  return 0;
}
