#include <bits/stdc++.h>
using namespace std;

int main() {
  long long n;
  cin >> n;

  long long a = sqrt(1.75 + 2 * n) - 0.5;
  a--;
  while ((a + 1) * (a + 2) / 2 <= n + 1) a++;
  cout << n + 1 - a;
}



#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define long long int;
typedef std::vector<ll> vi;
typedef pair<ll, ll> pi;
#define ull unsigned long long
#define F first
#define S second
#define PB push_back
#define MP make_pair
#define boht_tez ios::sync_with_stdio(false); cin.tie(0); cout.tie(0)
#define MAXN ll(1e5 + 123)
#define MAXINP ll (1e3 + 123)
#define MAX_SIZE 100000000
#define    DOD(i)  cout<<setprecision(i)<<fixed<<
#define MOD 1000000007ll
#define pi 3.1415926536



typedef pair<int, int> ii;
typedef vector<ii> vii;

ll n;

int main()
{

#ifndef ONLINE_JUDGE
	// for getting input from input.tx
	freopen("input1.txt", "r", stdin);
	// for writing output to output.txt
	freopen("output1.txt", "w", stdout);
#endif

	ll t = 1 ;
	//cin >> t;
	while (t--) {
		ll a, b;
		cin >> a >> b;
		ll x = a - b;
		double ans = (x * 100.00) / a;
		cout << ans;


	}
}