#define _CRT_SECURE_NO_WARNINGS
/*
⣿⡟⡡⠾⠛⠻⢿⣿⣿⣿⡿⠃⣿⡿⣿⠿⠛⠉⠠⠴⢶⡜⣦⡀⡈⢿⣿
⡿⢀⣰⡏⣼⠋⠁⢲⡌⢤⣠⣾⣷⡄⢄⠠⡶⣾⡀⠀⣸⡷⢸⡷⢹⠈⣿
⡇⢘⢿⣇⢻⣤⣠⡼⢃⣤⣾⣿⣿⣿⢌⣷⣅⡘⠻⠿⢛⣡⣿⠀⣾⢠⣿
⣷⠸⣮⣿⣷⣨⣥⣶⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡟⢁⡼⠃⣼⣿
⡟⠛⠛⠛⣿⠛⠛⢻⡟⠛⠛⢿⡟⠛⠛⡿⢻⡿⠛⡛⢻⣿⠛⡟⠛⠛⢿
⡇⢸⣿⠀⣿⠀⠛⢻⡇⠸⠃⢸⡇⠛⢛⡇⠘⠃⢼⣷⡀⠃⣰⡇⠸⠇⢸
⡇⢸⣿⠀⣿⠀⠛⢻⡇⢰⣿⣿⡇⠛⠛⣇⢸⣧⠈⣟⠃⣠⣿⡇⢰⣾⣿
⣿⣿⣿⠘⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⢋⣿⠙⣷⢸⣷⠀⣿⣿⣿
⣿⣿⣿⡇⢻⣿⣿⣿⡿⠿⢿⣿⣿⣿⠟⠋⣡⡈⠻⣇⢹⣿⣿⢠⣿⣿⣿
⣿⣿⣿⣿⠘⣿⣿⣿⣿⣯⣽⣉⣿⣟⣛⠷⠙⢿⣷⣌⠀⢿⡇⣼⣿⣿⣿
⣿⣿⣿⡿⢀⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣶⣤⡙⢿⢗⣀⣁⠈⢻⣿
*/
//#pragma GCC optimize("Ofast,unroll-loops")
//#pragma GCC target("avx2,bmi,bmi2,popcnt,lzcnt")
//Donald Trump pleese save this code
//Babahnineeleven will win IOI 2040
//Babahnineeleven will win IOI 2041
//Babahnineeleven will win IOI 2042
//Babahnineeleven will win IOI 2043
//Babahnineeleven will win IOI 2044
//Babahnineeleven will win IOI 2045
//Babahnineeleven will win IOI 2046
//Babahnineeleven will win IOI 2047
//Babahnineeleven will win IOI 2048
//Tanya Zadniprovska will win EGOI 2025
//Andrew Holod will NOT win IOI 2025
//Andrew Holod did not qualify to IOI 2025))))))))))
//Andrew Kholod will win ICPC WF 2026
//Andrew Pavlyk is best coder in Khmelnytski
//MoonSlay will NOT get Into IOI
#include <iostream>
#include <cstring>
#include <string>
#include <cmath>
#include <queue>
#include <bitset>
#include <stack>
#include <map>
#include <vector>
#include <set>
#include <algorithm>
#define endl '\n'
using namespace std;
FILE* stream;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair < int, int > pii;
typedef pair < ll, ll > pll;
typedef pair < ld, ld > pdd;
const long long DIM = 500007;
const ld eps = 1e-12;
const long long INF = 3e18;
const long long Bsize = 450;
const int mod = 1e9 + 7;
const long long NUMSZ = 500;
//ll n, opr;
/*
long long collisions(vector<long long> x) {
opr += x.size();
ll res = 0;
map < ll, ll > cnt;
for (auto val : x) {
res += cnt[val % n];
cnt[val % n]++;
}
return res;
}
*/
long long collisions(vector<long long> x);
int hack() {
int k = 31623;
vector < ll > tmp;
for (int i = 1; i <= k; i++) tmp.push_back(i);
ll col = collisions(tmp);
if (col != 0) {
for (int i = 1; i <= k; i++) {
ll cnt = (ll)i * (ll(k / i) * (ll(k / i) - 1) / 2);
cnt += (k / i) * (k % i);
if (cnt == col) return i;
}
}
int L = 2, R = k;
while (L < R) {
int mid = (L + R) >> 1;
vector < ll > x;
for (int i = 1; i <= k; i++) x.push_back(i);
for (ll i = L; i <= mid; i++) x.push_back(k * i);
if (collisions(x) > 0) R = mid;
else L = mid + 1;
}
ll val = k * (ll)L;
L = 1; R = k;
while (L < R) {
int mid = (L + R) >> 1;
vector < ll > x;
for (int i = L; i <= mid; i++) x.push_back(i);
x.push_back(val);
if (collisions(x) > 0) R = mid;
else L = mid + 1;
}
ll C = L;
return val - C;
}
/*
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#ifdef _DEBUG
freopen_s(&stream, "input.txt", "r", stdin);
freopen_s(&stream, "output.txt", "w", stdout);
#endif
n = 1e9;
cout << hack();
return 0;
}
*/
