#include <bits/stdc++.h>
using namespace std;
int x[] = {0,   4,   22,  27,  58,  85,  94,   121,  166, 202, 265,
           274, 319, 346, 355, 378, 382, 391,  438,  454, 483, 517,
           526, 535, 562, 576, 588, 627, 634,  636,  645, 648, 654,
           663, 666, 690, 706, 728, 729, 762,  778,  825, 852, 861,
           895, 913, 915, 922, 958, 985, 1086, 1111, 1165};
int main() {
  int a;
  cin >> a;
  cout << x[a];
  return 0;
}
