#include <bits/stdc++.h>
using namespace std;
int num[] = {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};
int main() {
  int a;
  scanf("%d", &a);
  printf("%d\n", num[a]);
}
