HZNU Training 8 for Zhejiang Provincial Competition 2020

#include<bits/stdc++.h>
#define rep(i,j,k) for(int i=(int)j;i<=(int)k;i++)
#define per(i,j,k) for(int i=(int)k;i>=(int)j;i++)
#define pb push_back
using namespace std;
typedef long long ll;
const int N=1e3+20;
int main(){
    int t;
    scanf("%d",&t);
    while(t--){
    ll x,y,z;
    scanf("%lld %lld %lld",&x,&y,&z);
    ll ans=x+y-z;
    if(x+y==z)ans=2e9;
    else if(ans<=x||ans<=z)ans=-1;
    printf("%lld\n",ans);
    
    }

    return 0;
}