#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
int main()
{
    ll n;
    cin>>n;
    ll i=1;
    ll ans=0;
    while(i)
    {
       if((i*(i+1))/2>=n)
       {
           ans=i;
           break;
       }
       i++;
    }
    cout<<ans<<endl;
    return 0;
}
#include <iostream>
#include <bits/stdc++.h>
#include <fstream>
using namespace std;
typedef long long ll;
typedef long double ld;
#define fast ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);

int main()
{
    fast
    int n, cnt = 0;
    cin >> n;
    if (n%100 == 0) n++,cnt++;
    while(n % 100)
        n++,cnt++;
    cout << cnt;
}
