NCPC-3

#include <iostream>
#include <cstdio>
#include <cmath>
#include <vector>

#define ul unsigned long long
using namespace std;
vector<int> vb;

int gcd(int a,int b)
{
	if(a%b==0)
	return b;
	else
	return gcd(b,a%b);
}

int main()
{
	int kase=1;
	int t,increment,lim;
	ul n,sum=0;
	cin>>t;
	while(t--)
	{
		cin>>n;
		vb.clear();
		lim = sqrt(n);
		if(n%2)
		increment = 2;
		else
		increment = 1;
		for(int i=1;i<=lim;i++)
		{
			if(n%i==0)
			{
				vb.push_back(i);
				if(i!=n/i)
				vb.push_back(n/i);
			}
		}
		int len=vb.size();
		sum = 0;
		for(int i=0;i<len;i++)
		{
			for(int j=0;j<len;j++)
			{
				sum += gcd(vb[i],vb[j]);
			}
		}
		printf("Case %d: ",kase++);
		printf("%llu\n",sum);
	}
	return 0;
}