题目描述
解方程
C++ 代码
#include<bits/stdc++.h>
#define endl '\n'
#define debug(a) cout<<#a<<"="<<a<<endl;
#define fast ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);
#define x first
#define y second
#define mm memset
#define int long long
using namespace std;
typedef long long LL;
typedef pair<int,int> PII;
void solve(){
int a,b,c,d;
cin >> a >> b >> c >> d;
int p = d - b;
int q = d - b - c + a;
if(p >= 0 && q >= 0) cout << p + q << endl;
else cout << -1 << endl;
}
signed main(){
fast
int T;
//T = 1;
cin >> T;
while(T --) solve();
return 0;
}