简单dfs
#include<iostream>
using namespace std;
int T;
int m,n;
int cnt;
int res;
void dfs(int e,int cnt,int ne)
{
if(cnt == n)
{
if(e == 0) res++;
return;
}
for(int i = ne;i<=m;i++) dfs(e-i,cnt+1,i);
}
int main()
{
cin>>T;
while(T--)
{
cin>>m>>n;
res = 0;
dfs(m,0,0);
cout<<res<<endl;
}
}