HDU——2056——Rectangles

#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
double x1,y1,x2,y2,x3,y3,x4,y4;
double a,b,c,d;
while(cin>>x1>>y1>>x2>>y2>>x3>>y3>>x4>>y4)
{
double sum=0;
if(x1>x2){double temp=x1;x1=x2;x2=temp;}
if(y1>y2){double temp=y1;y1=y2;y2=temp;}
if(x3>x4){double temp=x3;x3=x4;x4=temp;}
if(y3>y4){double temp=y3;y3=y4;y4=temp;}
if(x2<=x3||x1>=x4||y3>=y2||y1>=y4){sum=0;}
else
{
if(x1>x3)a=x1;else a=x3;
if(x2>x4)b=x4;else b=x2;
if(y1>y3)c=y1;else c=y3;
if(y2>y4)d=y4;else d=y2;
sum=(b-a)*(d-c);
}
cout<<fixed<<setprecision(2)<<sum<<endl;

}
return 0;
}