Submission #752606

#	Time	Username	Problem	Language	Result	Execution time	Memory
752606		bgnbvnbv	Asceticism (JOI18_asceticism)	C++14	49 / 100	84 ms	94396 KiB

asceticism

#include<bits/stdc++.h>
#define TASKNAME "codeforce"
#define pb push_back
#define pli pair<int,int>
#define fi first
#define se second
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL);
using namespace std;
using ll=long long;
const ll maxN=2e5;
const ll inf=1e18;
const ll mod=1e9+7;
ll dp[3005][3005],n,k;
void solve()
{
    cin >> n >> k;
    dp[1][0]=1;
    for(int i=2;i<=n;i++)
    {
        for(int j=0;j<=i-1;j++)
        {
            dp[i][j]=(j+1)*dp[i-1][j];
            if(j-1>=0) dp[i][j]+=(i-j)*dp[i-1][j-1];
            dp[i][j]%=mod;
        }
    }
    cout << dp[n][k-1]%mod;
}
int main()
{
    fastio
    //freopen(TASKNAME".INP","r",stdin);
    //freopen(TASKNAME".OUT","w",stdout);
    solve();
}

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