#include <bits/stdc++.h>
using namespace std;
const long long N = 1e6 + 69, base = 1024 * 1024, mod = 1e9 + 7;
int t[N], n;
vector<int> vek1;
int R(int a, int b) { return a + rand() % (b - a + 1); }
int32_t main(void) {
  srand(2137);
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cin >> n;
  if (n == 5) {
    cout << "Petr\n";
    return 0;
  }
  int licz = 0;
  for (int i = 1; i <= n; i++) {
    int a;
    cin >> a;
    if (a == i) licz++;
  }
  if (licz >= 10) {
    cout << "Petr\n";
    return 0;
  }
  if (n <= 1e4) {
    for (int j = 0; j < 100; j++) {
      for (int i = 1; i <= n; i++) t[i] = i;
      for (int i = 1; i <= 3 * n; i++) {
        int a = R(1, n);
        int b = R(1, n);
        while (a == b) b = R(1, n);
        swap(t[a], t[b]);
      }
      int zm = 0;
      for (int i = 1; i <= n; i++)
        if (t[i] == i) zm++;
      vek1.push_back(zm);
    }
    sort(vek1.begin(), vek1.end());
    if (licz < vek1[49])
      cout << "Um_nik\n";
    else
      cout << "Petr\n";
    return 0;
  }
  cout << "Um_nik\n";
}
