Submission #68825

#	Time	Username	Problem	Language	Result	Execution time	Memory
68825		IvanC	Asceticism (JOI18_asceticism)	C++17	49 / 100	139 ms	142788 KiB

asceticism

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;

const int MAXN = 3010;
const int MOD = 1e9 + 7;

ll dp[MAXN][MAXN];
int N,K;

ll solve(int dia,int grupos){
	if(dp[dia][grupos] != -1) return dp[dia][grupos];
	if(grupos == 0) return dp[dia][grupos] = 0;
	if(dia == 1) return dp[dia][grupos] = (grupos == 1);
	return dp[dia][grupos] = ((grupos)*solve(dia - 1,grupos) + (dia - grupos + 1)*solve(dia - 1,grupos - 1)) % MOD;
}

int main(){

	memset(dp,-1,sizeof(dp));
	cin >> N >> K;
	cout << solve(N,K) << endl;

	return 0;
}

• Subtask 1: 4 / 4
• Subtask 2: 20 / 20
• Subtask 3: 25 / 25
• Subtask 4: 0 / 51