三个加起来模7即可(注意周日的特判)

#include <bits/stdc++.h>
using namespace std;
#define ios ios::sync_with_stdio(false),cin.tie(0),cout.tie(0)
#define ll long long

int main()
{
	//freopen("","r",stdin);
	//freopen("","w",stdout);
	ios;
	int T; 
	cin>>T;
	while(T--)
	{
		ll x,y,z,ans;
		cin>>x>>y>>z;
		ans=(z+y+x)%7;
		if(ans==0)
			ans=7;
		cout<<ans<<endl;
	}
	return 0;
}