39 lines
744 B
C++
39 lines
744 B
C++
#include <iostream>
|
|
#include <string.h>
|
|
#include <stdio.h>
|
|
using namespace std;
|
|
typedef long long LL;
|
|
const int N=2005;
|
|
const LL MOD=1000000007;
|
|
LL C[N][N];
|
|
LL S[N][N];
|
|
void Init()
|
|
{
|
|
int i,j;
|
|
for(i=0;i<N;i++)
|
|
{
|
|
C[i][0]=1;
|
|
C[i][i]=1;
|
|
S[i][0]=0;
|
|
S[i][i]=1;
|
|
for(j=1;j<i;j++)
|
|
{
|
|
C[i][j]=(C[i-1][j]%MOD+C[i-1][j-1]%MOD)%MOD;
|
|
S[i][j]=((i-1)%MOD*S[i-1][j]%MOD+S[i-1][j-1]%MOD);
|
|
}
|
|
}
|
|
}
|
|
int main()
|
|
{
|
|
LL t,n,f,b,ans;
|
|
Init();
|
|
scanf("%I64d",&t);
|
|
while(t--)
|
|
{
|
|
scanf("%I64d%I64d%I64d",&n,&f,&b);
|
|
ans=C[f+b-2][f-1]%MOD*S[n-1][f+b-2]%MOD;
|
|
printf("%I64d\n",ans);
|
|
}
|
|
return 0;
|
|
}
|