1 #include <iostream>
 2 #include <algorithm>
 3 #include <stdio.h>
 4 using namespace std;
 5 typedef struct node
 6 {
 7     double x,y1,y2;
 8     int flag;
 9 } node;
10 typedef struct tree
11 {
12     double y1,y2,x;
13     double cover;
14     bool flag;
15 } treee;
16 node n[400];
17 treee tree[10000000];
18 double q[400];
19 bool cmp(node a,node b)
20 {
21     return a.x<b.x;
22 }
23 void build(int l,int r,int t)
24 {
25     tree[t].cover=0;
26     tree[t].flag=false;
27     tree[t].x=-1;
28     tree[t].y1=q[l];
29     tree[t].y2=q[r];
30     if(l+1==r)
31     {
32         tree[t].flag=true;
33         return ;
34     }
35     int m=(l+r)>>1;
36     build(l,m,t<<1);
37     build(m,r,t<<1|1);
38 }
39 double insert(double x,double y1,double y2,int t,int cover)
40 {
41     if(tree[t].y1>=y2||tree[t].y2<=y1)
42     {
43         return 0;
44     }
45     if(tree[t].flag)
46     {
47         if(tree[t].cover>0)
48         {
49             double sum=0,x1=tree[t].x;
50             sum=(x-x1)*(tree[t].y2-tree[t].y1);
51             tree[t].cover+=cover;
52             tree[t].x=x;
53             return sum;
54         }
55         else
56         {
57             tree[t].cover+=cover;
58             tree[t].x=x;
59             return 0;
60         }
61     }
62     return insert(x,y1,y2,t<<1,cover)+insert(x,y1,y2,t<<1|1,cover);
63 }
64 int main()
65 {
66     double x,y,xx,yy;
67     int m,t,i,ww=1;
68     while(~scanf("%d",&m)&&m)
69     {
70         t=1;
71         for(i=0; i<m; i++)
72         {
73             scanf("%lf%lf%lf%lf",&x,&y,&xx,&yy);
74             q[t]=y;
75             n[t].flag=1;
76             n[t].x=x;
77             n[t].y1=y;
78             n[t++].y2=yy;
79             q[t]=yy;
80             n[t].flag=-1;
81             n[t].x=xx;
82             n[t].y1=y;
83             n[t++].y2=yy;
84         }
85         sort(n+1,n+t,cmp);
86         sort(q+1,q+t);
87         build(1,t-1,1);
88         double sum=0;
89         for(i=1; i<t; i++)
90         {
91             sum+=insert(n[i].x,n[i].y1,n[i].y2,1,n[i].flag);
92         }
93         cout<<"Test case #"<<ww++<<endl;
94         cout<<"Total explored area: ";
95         printf("%.2lf\n\n",sum);
96     }
97 }