一样呀，我也就过了这一道... 而且两小时撑死做3道题

 #include <iostream>
 #include <vector>
 #include <set>
 using namespace std;

 int main( )
 {
     int t,start,step;
     cin>>t;
     for(int i=0;i < t; ++i){
         cin>>start>>step;
         int area1= 0x80000000,area2=0x80000000;
         if(start < step){
             area1 = start*(step-start);
         }   
         double d = (double)step/4;
         int l = (int)d; 
         int r = (int)(d+1);
         int height = (d-(double)l) > ((double)r- d)? r: l;     
         area2 = height*(step-(height<<1));

         cout<<max(area1, area2)<<endl;
     } 
     return 0;
 }