#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  int a[n];
  for (int i = 0; i < n; i++) cin >> a[i];
  if (n == 1 && a[0] == 1)
    cout << "P";
  else if (n == 1 && a[0] > 1)
    cout << "NO";
  else {
    for (int i = 0; i < n - 1; i++) {
      for (int j = 0; j < a[i]; j++) cout << "PRL";
      cout << 'R';
    }
    for (int i = 0; i < a[n - 1]; i++) cout << "PLR";
  }
  return 0;
}
