Please tell which test case is not satisfied here

#1

#include<bits/stdc++.h>

using namespace std;

long long binomial_coeff(long long n,long long r)
{
r=min(r,n-r);
long long prod=1;
for(long long i=0;i<r;++i)
{
prod*=n-i;
prod/=(i+1);
}
return prod;
}
int main()
{
int T=0;
cin>>T;
long long N=0,K=0;
for(int t=0;t<T;t++)
{
cin>>N;
cin>>K;
cout<<binomial_coeff(N-1, K-1)<<endl;
}
return 0;
}

#2

@goyal431 You need to use bigint() to avoid overflow, long long int isn’t sufficient.

#3

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