제출 #774642

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
774642		Ozy	Kućice (COCI21_kucice)	C++17	10 / 110	1 ms	340 KiB

Main

#include <iostream>
#include <bits/stdc++.h>
using namespace std;
#define lli long long int
#define debug(a) cout << #a << " = " << a << endl
#define debugsl(a) cout << #a << " = " << a << ", "
#define rep(i,a,b) for(lli i = (a); i <= (b); i++)
#define repa(i,a,b) for(lli i = (a); i >= (b); i--)
#define pll pair<lli,lli>

#define mod 1000000007

lli a,b,n,res,act;

lli expo(lli num, lli pot) {

    lli res = 1;
    while (pot) {
        if (pot&1) {
            res *= num;
            res %= mod;
        }
        num *= num;
        num %=mod;
        pot /= 2;
    }
    return res;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    cin >> n;
    rep(i,1,n) cin >> a >> b;

    act = 1;
    res = 0;
    rep(i,0,n) {
        res += act*i;
        res %= mod;

        act *= (n-i);
        act %= mod;

        act *= expo(i+1,mod-2);
        act %= mod;


        //debugsl(act);
        //debugsl(i);
        //debug(res);
    }
    cout << res;

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 30
• Subtask 3: 0 / 10
• Subtask 4: 0 / 30
• Subtask 5: 0 / 30