Code not getting accepted(MARBLES)

#1

#include<bits/stdc++.h>
using namespace std;
#define ll unsigned long long
ll int calculate(int n,int k)
{
ll int mul=1,kmul=1;
int ok=k;
for(ll int i=n-1;i>n-k;i–)
{
mul=muli;
kmul=kmul(–ok);
}
return mul/kmul;
}
int main()
{
ll int t;
cin>>t;
while(t–)
{
ll int n,k;
cin>>n>>k;
cout<<calculate(n,k)<<endl;
}
return 0;
}

#2

Answer can overflow 64-bit integer.
Refer this for big int

#3

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