What's wrong in my code?

#1

#include<bits/stdc++.h>
using namespace std;
long long int kroot(int n,int k)
{
long long int res=1;
long long int s=0,e=n;
while(s<=e)
{
long long int mid=(s+e)/2;
if(pow(mid,k)==n)
{
res= mid;
break;
}
else if(pow(mid,k)<n)
{
res=mid;
s=mid+1;
}
else
{
e=mid-1;
}
}
return res;
}
int main() {
int t;
cin>>t;
while(t–)
{
long long int n,k;
cin>>n>>k;
long long int ans=kroot(n,k);
cout<<ans<<endl;
}
return 0;
}

#2

Use long long int in formal parameters.