Kortit II

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define N 101
#define M 1000000007

int t,n,a,b;
ll C[N][N],f[N][N],ncr[N][N],F[N];

int main(){
	cin.tie(0)->sync_with_stdio(0);

	F[0]=1;
	for(int i=1;i<N;++i) F[i]=i*F[i-1]%M;

	for(int i=0;i<N;++i){
		ncr[i][0]=1;
		for(int j=1;j<=i;++j) ncr[i][j]=(ncr[i-1][j-1]+ncr[i-1][j])%M;
	}

	C[0][0]=1;
	for(int n=2;n<N;++n){
		C[n][1]=1;
		for(int k=2;k<=n;++k) C[n][k]=(k*C[n-1][k]+(n-k)*C[n-1][k-1])%M;
	}

	f[0][0]=1;
	for(int n=2;n<N;++n){
		f[n][1]=f[n][n-1]=1;
		for(int k=2;k<n-1;++k){
			ll S=C[n][k];
			for(int i=1;i<n;++i){
				ll s=0;
				for(int j=1;j<k;++j) s+=C[i][j]*f[n-i][k-j]%M;
				S+=ncr[n-1][i-1]*s%M;
				S%=M;
			}
			f[n][k]=S;
		}
	}

	cin>>t;
	while(t--){
		cin>>n>>a>>b;
		if(a+b>n){
			cout<<"0\n";
			continue;
		}
		ll r=f[a+b][a]*ncr[n][n-a-b]%M*F[n]%M;
		cout<<r<<'\n';
	}
}

Test 1

Group: 1, 2, 3, 4, 5

Verdict: ACCEPTED

Test 2

Group: 2, 3, 4, 5

Verdict: ACCEPTED

Test 3

Group: 3, 4, 5

Verdict: ACCEPTED

Test 4

Group: 4, 5

Verdict: WRONG ANSWER

Test 5

Group: 5

Verdict: RUNTIME ERROR

Test 6

Group: 5

Verdict: RUNTIME ERROR