第三题
#include <iostream>
using namespace std;
int main() {
long long T;
cin >> T;
while (T--) {
long long n, l, r;
cin >> n >> l >> r;
long long needadd = 0;
long long needmin = 0;
long long canadd = 0;
long long canmin = 0;
for (long long i = 0; i < n; i++) {
long long t;
cin >> t;
if (t < l) needadd += l - t;
if (t > r) needmin += t - r;
if (t > l) canmin += t - l;
if (t < r) canadd += r - t;
}
// cout<<needadd<<" "<<canadd<<" "<<needmin<<" "<<canmin<<endl;
if (needadd > canmin || needmin > canadd) cout << -1 << endl;
else cout << max(needadd, needmin) << endl;
}
}
