답안 #20062

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
20062 2016-02-25T08:59:22 Z emppu 카드 (kriii4_Z) C++14
0 / 100
48 ms 142628 KB
#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <cstring>
#include <cassert>

#include <algorithm>
#include <vector>
#include <string>
#include <set>
#include <map>
#include <queue>
#include <deque>
#include <list>
#include <bitset>
#include <tuple>

using namespace std;

#define f0(_X,_Y) for(int (_X)=0;(_X)<(_Y);++(_X))
#define f1(_X,_Y) for(int (_X)=1;(_X)<=(_Y);++(_X))
#define ff(_X,_Y,_Z) for(int (_X)=(_Y);(_X)<=(_Z);++(_X))
#define fF(_X,_Y,_Z) for(int (_X)=(_Y);(_X)<(_Z);++(_X))
#define rf0(_X,_Y) for(int _X=(_Y)-1;(_X)>=0;--(_X))
#define rf1(_X,_Y) for(int _X=(_Y);(_X)>0;--(_X))
#define rff(_X,_Y,_Z) for(int _X=(_Y);(_X)>=(_Z);--(_X))
#define rfF(_X,_Y,_Z) for(int _X=(_Y);(_X)>(_Z);--(_X))
#define PRT(_X) std::cout<< #_X ": "<<_X<<std::endl;

#define scan1(_X) scanf("%d",&_X);
#define scan2(_X,_Y) scanf("%d%d",&_X,&_Y);
#define scan3(_X,_Y,_Z) scanf("%d%d%d",&_X,&_Y,&_Z);
#define define1(_1) int _1; scan1(_1)
#define define2(_1,_2) int _1,_2; scan2(_1,_2)
#define define3(_1,_2,_3) int _1,_2,_3; scan3(_1,_2,_3)
#define EXPAND(_1) _1
#define SELECT(_1,_2,_3,_4,NAME,...) NAME
#define scan(...) EXPAND(SELECT(__VA_ARGS__, scan4, scan3, scan2, scan1)(__VA_ARGS__))
#define define(...) EXPAND(SELECT(__VA_ARGS__, define4, define3, define2, define1)(__VA_ARGS__))
#define print(_X) printf("%d\n",_X)
#define PAIR_STRUCT(_T,_X,_Y,...) struct _T{int _X,_Y,##__VA_ARGS__; bool friend operator < (const _T &p, const _T &q){if(p._X!=q._X) return p._X<q._X; return p._Y<q._Y;}}

typedef long long ll;

const int MOD = 1000000007;
ll mul(ll a, ll b){return a*b%MOD;}
ll add(ll a, ll b){return (a+b)%MOD;}


ll inv(ll a, ll b=MOD)
{
    ll s = 0;  ll  old_s = 1;
    ll r = b;  ll  old_r = a;
    while (r!=0)
    {
        ll quotient = old_r / r;
        tie(old_r, r) = make_tuple(r, old_r - quotient * r);
        tie(old_s, s) = make_tuple(s, old_s - quotient * s);
    }
    ll inv = old_s%MOD;
    if(inv<0) inv += MOD;
    return inv;
}

const int N = 3003;
ll s[N][N];
ll d[N][N];

int main()
{
	define(n,l);
	int need=0;
	f1(i,n)
	{
		define(d2);
		if(d2) ++need;
	}
	ll invn = inv(n);
	d[0][0]=1;
	f1(i,l)
	{
		f1(j,i)
		{
			if(j>n) break;
			d[i][j] = mul( add( mul(d[i-1][j],j) ,mul(d[i-1][j-1],(n-j+1)) ) ,invn);
		}
	}


	printf("%lld\n",d[l][n]);
	return 0;
}
# 결과 실행 시간 메모리 Grader output
1 Incorrect 48 ms 142628 KB Output isn't correct
2 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Halted 0 ms 0 KB -