#include <bits/stdc++.h>
using namespace std;

#define SZ(a) (int)a.size()
#define ALL(a) a.begin(), a.end()
#define FOR(i, a, b) for (int i = (a); i<(b); ++i)
#define RFOR(i, b, a) for (int i = (b)-1; i>=(a); --i)
#define MP make_pair
#define PB push_back
#define F first
#define S second
#define FILL(a, b) memset(a, b, sizeof(a))

typedef long long LL;
typedef pair<int, int> PII;
typedef vector<int> VI;

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	int t;
	cin >> t;
	while (t--) {
		int x, y, z;
		cin >> x >> y >> z;
		int d = x + y - z;
		if (d < 0) {
			cout << "-1\n";
		}
		else if (d == 0) {
			cout << z + 1 << "\n";
		}
		else if (d > max(x, z)) {
			cout << d << "\n";
		}
		else {
			cout << "-1\n";
		}
	}
	return 0;
}