#include<bits/stdc++.h>
using namespace std;
int x[5],t;
int main()
{
	cin>>t;
	while(t--)
	{
		cin>>x[1]>>x[2]>>x[3];
		sort(x+1,x+4);
		int a=x[2]-x[1],b=x[3]-x[2];
		if(a%2||b%2||(a-b)%6) cout<<-1<<"\n";
		else cout<<min(a,b)/2+abs(a-b)/3<<"\n";
	}
	return 0;
}