結果

問題 No.243 出席番号(2)
ユーザー anta
提出日時 2015-07-10 22:32:23
言語 C++11
(gcc 4.8.5)
結果
AC  
実行時間 155 ms
コード長 2,934 Byte
コンパイル時間 530 ms
使用メモリ 1,592 KB
最終ジャッジ日時 2019-09-18 13:45:34

テストケース

テストケース表示
入力 結果 実行時間
使用メモリ
sample1.txt AC 2 ms
1,504 KB
sample2.txt AC 2 ms
1,504 KB
sample3.txt AC 3 ms
1,504 KB
test1.txt AC 8 ms
1,528 KB
test2.txt AC 8 ms
1,524 KB
test3.txt AC 7 ms
1,524 KB
test4.txt AC 8 ms
1,528 KB
test5.txt AC 8 ms
1,528 KB
test6.txt AC 22 ms
1,540 KB
test7.txt AC 19 ms
1,540 KB
test8.txt AC 18 ms
1,540 KB
test9.txt AC 18 ms
1,540 KB
test10.txt AC 22 ms
1,540 KB
test11.txt AC 43 ms
1,556 KB
test12.txt AC 37 ms
1,560 KB
test13.txt AC 36 ms
1,556 KB
test14.txt AC 36 ms
1,556 KB
test15.txt AC 49 ms
1,556 KB
test16.txt AC 74 ms
1,576 KB
test17.txt AC 64 ms
1,572 KB
test18.txt AC 61 ms
1,572 KB
test19.txt AC 62 ms
1,568 KB
test20.txt AC 93 ms
1,576 KB
test21.txt AC 113 ms
1,588 KB
test22.txt AC 97 ms
1,588 KB
test23.txt AC 93 ms
1,592 KB
test24.txt AC 93 ms
1,588 KB
test25.txt AC 155 ms
1,592 KB
test26.txt AC 3 ms
1,504 KB
test27.txt AC 3 ms
1,504 KB
test28.txt AC 3 ms
1,508 KB
test29.txt AC 3 ms
1,508 KB
test30.txt AC 3 ms
1,508 KB
テストケース一括ダウンロード

ソースコード

diff #
#include <string>
#include <vector>
#include <algorithm>
#include <numeric>
#include <set>
#include <map>
#include <queue>
#include <iostream>
#include <sstream>
#include <cstdio>
#include <cmath>
#include <ctime>
#include <cstring>
#include <cctype>
#include <cassert>
#include <limits>
#include <functional>
#include <bitset>
#define rep(i,n) for(int (i)=0;(i)<(int)(n);++(i))
#define rer(i,l,u) for(int (i)=(int)(l);(i)<=(int)(u);++(i))
#define reu(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i))
#if defined(_MSC_VER) || __cplusplus > 199711L
#define aut(r,v) auto r = (v)
#else
#define aut(r,v) __typeof(v) r = (v)
#endif
#define each(it,o) for(aut(it, (o).begin()); it != (o).end(); ++ it)
#define all(o) (o).begin(), (o).end()
#define pb(x) push_back(x)
#define mp(x,y) make_pair((x),(y))
#define mset(m,v) memset(m,v,sizeof(m))
#define INF 0x3f3f3f3f
#define INFL 0x3f3f3f3f3f3f3f3fLL
using namespace std;
typedef vector<int> vi; typedef pair<int,int> pii; typedef vector<pair<int,int> > vpii; typedef long long ll;
template<typename T, typename U> inline void amin(T &x, U y) { if(y < x) x = y; }
template<typename T, typename U> inline void amax(T &x, U y) { if(x < y) x = y; }

template<int MOD>
struct ModInt {
	static const int Mod = MOD;
	unsigned x;
	ModInt(): x(0) { }
	ModInt(signed sig) { int sigt = sig % MOD; if(sigt < 0) sigt += MOD; x = sigt; }
	ModInt(signed long long sig) { int sigt = sig % MOD; if(sigt < 0) sigt += MOD; x = sigt; }
	int get() const { return (int)x; }
	
	ModInt &operator+=(ModInt that) { if((x += that.x) >= MOD) x -= MOD; return *this; }
	ModInt &operator-=(ModInt that) { if((x += MOD - that.x) >= MOD) x -= MOD; return *this; }
	ModInt &operator*=(ModInt that) { x = (unsigned long long)x * that.x % MOD; return *this; }
	ModInt &operator/=(ModInt that) { return *this *= that.inverse(); }
	
	ModInt operator+(ModInt that) const { return ModInt(*this) += that; }
	ModInt operator-(ModInt that) const { return ModInt(*this) -= that; }
	ModInt operator*(ModInt that) const { return ModInt(*this) *= that; }
	ModInt operator/(ModInt that) const { return ModInt(*this) /= that; }
	
	ModInt inverse() const {
		signed a = x, b = MOD, u = 1, v = 0;
		while(b) {
			signed t = a / b;
			a -= t * b; std::swap(a, b);
			u -= t * v; std::swap(u, v);
		}
		if(u < 0) u += Mod;
		ModInt res; res.x = (unsigned)u;
		return res;
	}
};
typedef ModInt<1000000007> mint;

int main() {
	int N;
	while(cin >> N) {
		vi A(N);
		rep(i, N) cin >> A[i];
		vi cnt(N, 0);
		rep(i, N) if(A[i] < N)
			++ cnt[A[i]];
		vector<mint> dp(N+2), ndp;
		dp[0] = 1;
		rep(i, N) {
			ndp.assign(N+2, mint());
			rer(j, 0, N) {
				mint x = dp[j];
				if(x.get() == 0) continue;
				ndp[j] += x;
				ndp[j+1] += x * cnt[i];
			}
			dp.swap(ndp);
		}
		mint ans;
		rer(j, 0, N) {
			mint x = dp[j];
			rep(k, N - j) x *= N - j - k;
			if(j % 2 == 0) ans += x; else ans -= x;
		}
		printf("%d\n", ans.get());
	}
	return 0;
}
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