Submission #21162

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
21162	2017-04-06T19:57:38 Z	gs14004	Hexagon travel (kriii1_H)	C++11	1 / 1	209 ms	2112 KB

H

#include <bits/stdc++.h>
using namespace std;
typedef long long lint;
typedef long double llf;
typedef pair<int, int> pi;

const int mod = 1e9 + 7;

lint ipow(lint x, lint p){
	lint ret = 1, piv = x % mod;
	while(p){
		if(p&1) ret *= piv;
		piv *= piv;
		ret %= mod;
		piv %= mod;
		p >>= 1;
	}
	return ret % mod;
}


int l, r, m;
int dp[2][2005][3][2];

int main(){
	cin >> l >> r >> m;
	lint fact = 1;
	for(int i=1; i<=l+r; i++) fact = (fact * i) % mod;
	for(int i=1; i<=l; i++) fact = (fact * ipow(i, mod-2)) % mod;
	for(int i=1; i<=r; i++) fact = (fact * ipow(i, mod-2)) % mod;
	l += r;
	dp[0][0][0][0] = 1;
	for(int i=0; i<=l; i++){
		for(int j=0; j<=m; j++){
			if(i + j == 0) continue;
			for(int k=0; k<3; k++){
				for(int l=0; l<2; l++){
					dp[i%2][j][k][l] = 0;
					if(i) dp[i%2][j][k][l] += dp[(i-1)%2][j][k][l^1];
					if(j) dp[i%2][j][k][l] += dp[i%2][j-1][(k + (l ? 1 : 2)) % 3][l];
					dp[i%2][j][k][l] %= mod;
				}
			}
		}
	}
	for(int i=1; i<=3; i++){
		lint ans = dp[l%2][m][i%3][0] + dp[l%2][m][i%3][1];
		ans *= fact;
		ans %= mod;
		cout << ans << endl;
	}
}

Subtask #1

1.0 / 1.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	2112 KB	Output is correct
2	Correct	0 ms	2112 KB	Output is correct
3	Correct	0 ms	2112 KB	Output is correct
4	Correct	0 ms	2112 KB	Output is correct
5	Correct	0 ms	2112 KB	Output is correct
6	Correct	0 ms	2112 KB	Output is correct
7	Correct	0 ms	2112 KB	Output is correct
8	Correct	0 ms	2112 KB	Output is correct
9	Correct	9 ms	2112 KB	Output is correct
10	Correct	209 ms	2112 KB	Output is correct
11	Correct	123 ms	2112 KB	Output is correct
12	Correct	66 ms	2112 KB	Output is correct
13	Correct	23 ms	2112 KB	Output is correct
14	Correct	66 ms	2112 KB	Output is correct
15	Correct	66 ms	2112 KB	Output is correct
16	Correct	19 ms	2112 KB	Output is correct
17	Correct	53 ms	2112 KB	Output is correct
18	Correct	66 ms	2112 KB	Output is correct
19	Correct	26 ms	2112 KB	Output is correct
20	Correct	39 ms	2112 KB	Output is correct