text: #include <iostream>
  #include <cmath>
  using namespace std;
  int main()
  {
      int n,i,count=0,j;
      cin >> n;
      for(i=1;i<=pow(n,0.5);i++)
      {
          for(j=i+1;i*j<=n;j++)
              count ++;
      }
      count += (int)pow(n,0.5);
      cout << count << endl;
      return 0;
  }
  
  