HDU 1194 - Beat the Spread!

给两数之和和两数之差，求两数，两数还必须同奇偶

 #include <iostream>
 using namespace std;
 int main()
 {
     int a,b,t;
     cin>>t;
     while(t--)
     {
         cin>>a>>b;
         int x = ( a + b ) / ;
         int y = ( a - b ) / ;
         if((a-b)%||(a+b)%||x<||y<) puts("impossible");
         else cout<<x<<" "<<y<<endl;
     }
 }