UVa 11743 - Credit Check

// UVa 11743 - Credit Check
#include <iostream>
using namespace std;

int main() {
	int cases;
	cin >> cases;
	for (; cases > 0; cases--) {
		int sum = 0;
		for (int i = 0; i < 4; i++) {
			int a;
			cin >> a;
			sum += (a % 10) + (a / 10 % 10) * 2 + (a / 100 % 10) + (a / 1000) * 2;
			if ((a / 10 % 10) * 2 >= 10)
				sum -= 9;
			if ((a / 1000) * 2 >= 10)
				sum -= 9;
		}
		cout << (sum % 10 != 0 ? "Invalid" : "Valid") << endl;

	}
	return 0;
}