1368B - Codeforces Subsequences - CodeForces Solution

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define mod 1000000007

void solve()
{
    int n;
    cin >> n;

    string cf = "codeforces";
    // int k = ceil(pow(n, 1.0/10));
    vector<int> v(10, 1);
    int i = 0;
    int k = 1;
    while(k < n) {
        k /= v[i];
        v[i]++;
        k *= v[i];
        i = (++i) % 10;
    }

    for(int i = 0; i < 10; i++) {
        while(v[i]--)   cout << cf[i];
    }
}

signed main()
{
#ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

    // write code here
    int t = 1;
    // cin >> t;

    while (t--)
    {
        solve();
    }
}