#include <bits/stdc++.h>
#pragma comment(linker, "/stack:200000000")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("unroll-loops")
using namespace std;
template <typename T>
constexpr int infValue =
    std::is_same<T, int>::value ? 2000100007 : 8600000000000000007ll;
template <typename T>
constexpr int maxValue =
    std::is_same<T, int>::value ? 1000000007 : 1000000000000000001ll;
const int INF = infValue<int>;
const long long MOD = 1000000007ll;
const double EPS = 1e-6;
const int MAX = maxValue<int>;
int n, cnt;
int a[1000110], idx[1000110];
int main(void) {
  scanf("%d", &n);
  for (register int i = 1; i <= n; ++i) scanf("%d", a + i), idx[a[i]] = i;
  for (register int i = 1; i <= n; ++i) {
    if (a[i] != i) {
      ++cnt;
      int v = a[i];
      swap(a[i], a[idx[i]]);
      idx[v] = idx[i];
      idx[i] = i;
    }
  }
  puts(cnt & 1 && n & 1 || !(n & 1) && !(cnt & 1) ? "Petr" : "Um_nik");
  return 0;
}
