Submission #19670

#	Time	Username	Problem	Language	Result	Execution time	Memory
19670		tonyjjw	창문 (kriii4_C)	C++14	3 / 100	0 ms	1720 KiB

C

//*
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <time.h>
#include <stdlib.h>
#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <string>
#include <numeric>
#include <functional>
#define MOD 1000000007
#define MAX 0x3f3f3f3f
#define MAX2 0x3f3f3f3f3f3f3f3fll
#define ERR 1e-10
#define mp make_pair
#define all(x) (x).begin(), (x).end()
#pragma warning(disable:4996)
using namespace std;

typedef long long ll;
typedef long double ldb;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<double, double> pdd;

ll mul_inv(ll a, ll b=MOD)
{
	ll b0=b, t, q;
	ll x0=0, x1=1;
	if(b == 1) return 1;
	while(a > 1)
	{
		q=a/b;
		t=b, b=a%b, a=t;
		t=x0, x0=x1-q*x0, x1=t;
	}
	if(x1 < 0) x1+=b0;
	return x1;
}


ll n, m;

ll ij, iij, ijj, iijj;
ll n1, n2, m1, m2;

int main()
{
	int i, j, k;
	cin>>n>>m;
	n%=MOD, m%=MOD;
	n1=n*(n+1)/2%MOD;
	m1=m*(m+1)/2%MOD;
	n2=n*(n+1)%MOD*(2*n+1)%MOD*mul_inv(6)%MOD;
	m2=m*(m+1)%MOD*(2*m+1)%MOD*mul_inv(6)%MOD;
	ij=n1*m1%MOD;
	iij=n2*m1%MOD;
	ijj=n1*m2%MOD;
	iijj=n2*m2%MOD;
	ll ans=(n+1)%MOD*(m+1)%MOD*ij%MOD;
	ans+=-(m+1)*iij%MOD;
	ans+=-(n+1)*ijj%MOD;
	ans+=iijj%MOD;
	ans%=MOD;
	ans*=9, ans%=MOD;
	ans+=MOD, ans%=MOD;
	ans*=mul_inv(ij);
	ans%=MOD;
	cout<<ans;
	return 0;
}
//*/

• Subtask 1: 3 / 3
• Subtask 2: 0 / 97