#include<iostream>

using namespace std;

int main()
{
  int n;
  cin>>n;
  cout<<n-1;
  return 0; 
}
#include <iostream>
using namespace std;
unsigned long long div_cnt[2][12] = {0};
int main()
{
  int L;
  cin >> L;
  div_cnt[1][0] = 1;
  for (int i = 1; i < L; i++) {
    for (int j = 0; j < 12; j++) {
      div_cnt[0][j] = div_cnt[1][j];
    }
    for (int j = 1; j < 12; j++) {
      div_cnt[1][j] = div_cnt[0][j-1]+div_cnt[0][j];
    }
  }
  cout << div_cnt[1][11] << endl;
  return 0;
}
