Submission #1817202

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Source Code Expand

#include<bits/stdc++.h>
using namespace std;
const int mod=1000000007;
const int maxn=305;
long long dp[maxn][maxn][maxn];// 已经有i天了，连接了j个点的双联通 k个点还没有双联通 的方案数。
int main()
{
    memset(dp,0,sizeof(dp));
    dp[1][1][0]=1;
    int n,m;
    scanf("%d%d",&n,&m);
    m++;
    if(m<n){
        puts("0");
        return 0;
    }
    for(int i=1;i<=m;i++)
    {
        for(int j=1;j<=n;j++)
        {
            for(int k=0;k+j<=n;k++)
            {
                if(dp[i][j][k]==0) continue;
                dp[i+1][j+k][0]=(dp[i+1][j+k][0]+dp[i][j][k]*j)%mod;
                dp[i+1][j][k]=(dp[i+1][j][k]+dp[i][j][k]*k)%mod;
                dp[i+1][j][k+1]=(dp[i+1][j][k+1]+dp[i][j][k])%mod;
            }
        }
    }
    long long ans=dp[m][n][0];
    for(int i=2;i<n;i++)
        ans=(ans*i)%mod;
    printf("%lld\n",ans);
    return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:11:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&n,&m);
                        ^

Judge Result