1 #include<iostream>
  2 #include<cstdio>
  3 #include<cmath>
  4 #include<map>
  5 #include<cstdlib>
  6 #include<vector>
  7 #include<set>
  8 #include<queue>
  9 #include<cstring>
 10 #include<string.h>
 11 #include<algorithm>
 12 #define INF 0x3f3f3f3f
 13 typedef long long ll;
 14 typedef unsigned long long LL;
 15 using namespace std;
 16 const int N=1000+100;
 17 double x[2*N];
 18 struct Edge{
 19     double l,r;
 20     double h;
 21     int flag;
 22 }edge[2*N];
 23 struct node{
 24     int l,r;
 25     int s;
 26     double len;
 27 }tree[N*8];
 28 bool cmp(Edge x,Edge y){
 29     return x.h<y.h;
 30 }
 31 void pushup(int pos){
 32     if(tree[pos].s)tree[pos].len=x[tree[pos].r+1]-x[tree[pos].l];
 33     else if(tree[pos].l==tree[pos].r)tree[pos].len=0;
 34     else{
 35         tree[pos].len=tree[pos<<1].len+tree[pos<<1|1].len;
 36     }
 37 }
 38 void build(int l,int r,int pos){
 39     tree[pos].l=l;tree[pos].r=r;
 40     tree[pos].s=0;tree[pos].len=0;
 41     if(tree[pos].l==tree[pos].r)return;
 42     int mid=(tree[pos].l+tree[pos].r)>>1;
 43     build(l,mid,pos<<1);
 44     build(mid+1,r,pos<<1|1);
 45 }
 46 void update(int l,int r,int pos,int xx){
 47     if(tree[pos].l==l&&tree[pos].r==r){
 48         tree[pos].s=tree[pos].s+xx;
 49         pushup(pos);
 50         return;
 51     }
 52     int mid=(tree[pos].l+tree[pos].r)>>1;
 53     if(r<=mid)update(l,r,pos<<1,xx);
 54     else if(l>mid)update(l,r,pos<<1|1,xx);
 55     else{
 56         update(l,mid,pos<<1,xx);
 57         update(mid+1,r,pos<<1|1,xx);
 58     }
 59     pushup(pos);
 60 }
 61 int main(){
 62     int n;
 63     int tt=0;
 64     while(scanf("%d",&n)!=EOF){
 65         tt++;
 66         if(n==0)break;
 67         int t=0;
 68         for(int i=0;i<n;i++){
 69             double x1,x2,y1,y2;
 70             scanf("%lf%lf%lf%lf",&x1,&y1,&x2,&y2);
 71             Edge &t1=edge[t];Edge &t2=edge[t+1];
 72             t1.l=t2.l=x1;t1.r=t2.r=x2;
 73             t1.h=y1;t2.h=y2;
 74             t1.flag=1;t2.flag=-1;
 75             x[t]=x1;x[t+1]=x2;
 76             t=t+2;
 77         }
 78         sort(edge,t+edge,cmp);
 79         sort(x,x+t);
 80         int k=1;
 81         for(int i=1;i<t;i++){
 82             if(x[i]!=x[i-1]){
 83                 x[k++]=x[i];
 84             }
 85         }
 86         //cout<<1<<endl;
 87         build(0,k-1,1);
 88         //cout<<2<<endl;
 89         double ans=0.0;
 90         //cout<<t<<endl;
 91         for(int i=0;i<t;i++){
 92             int l=lower_bound(x,x+k,edge[i].l)-x;
 93             int r=lower_bound(x,x+k,edge[i].r)-x-1;
 94             update(l,r,1,edge[i].flag);
 95             ans=ans+(edge[i+1].h-edge[i].h)*tree[1].len;
 96             //cout<<ans<<endl;
 97         }
 98         printf("Test case #%d\n",tt);
 99         printf("Total explored area: %.2f\n\n",ans);
100         //cout<<ans<<endl;
101     }
102 }