#include 

using namespace std;

int main()
{
    int n;
    cin>>n;
    int m[n];
    for(int i=0;i>m[i];
        m[i] += 1;

    }
    int zbir = 0;
    int i = 0;
    while(zbir < n) {
        zbir += m[i];
        i++;
    }
    cout << i << endl;
    return 0;
}