XDU_1064:Desolator in RA2

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 typedef long long LL;
 4 
 5 struct point
 6 {
 7     LL x,y;
 8 };
 9 
10 LL S(LL r)
11 {
12     LL d=2*r+1;
13     return (d*d+1)/2;
14 }
15 
16 LL xxx(point A,point B)
17 {
18     LL x=abs(A.x+A.y-B.x-B.y)+1;
19     LL y=abs(A.x-A.y-B.x+B.y)+1;
20     return (x*y+1)/2;
21 }
22 
23 
24 int main()
25 {
26     LL x1,x2,y1,y2,r,x,y;
27     while(cin>>x1>>y1>>x2>>y2>>r)
28     {
29         point p;
30         p.x=x=abs(x1-x2);
31         p.y=y=abs(y1-y2);
32         if(p.x+p.y>2*r)
33         {
34             cout<<2*S(r)<<‘\n‘;
35             continue;
36         }
37         point A,B;
38         if(abs(x)+abs(y-r)<=r)
39         {
40             A.x=0,A.y=r;
41             B.x=x,B.y=y-r;
42         }
43         else
44         {
45             A.x=r,A.y=0;
46             B.x=x-r,B.y=y;
47         }
48         cout<<2*S(r)-xxx(A,B)<<‘\n‘;
49     }
50 }