#include<iostream>  
#include<cstdio>  
#include<algorithm>
#define N 300 
using namespace std;
double y[N]; 
struct Node{  
    double x;double y1;double y2;  
    int flag;  
}node[N];  
struct node{  
    int l;int r;double ml;double mr;int s;double len;  
}a[N*3];
bool cmp(Node a,Node b){  
    return a.x-b.x<0.0000001;  
}   
void build(int i,int left,int right){  
    a[i].l=left;  
    a[i].r=right;  
    a[i].ml=y[left];  
    a[i].mr=y[right];  
    a[i].s=0;  
    a[i].len=0;  
    if(a[i].l+1==a[i].r){  
        return ;  
    }  
    int mid=(left+right)>>1;  
    build(i*2,left,mid);  
    build(i*2+1,mid,right);//建树时注意这里不是mid+1，因为做相减的时候如果mid+1这么建回到值左孩子的右边与有孩子的左边无法进行运算  
}  
void callen(int i){  
  
    if(a[i].s>0){//注意这里不是所有边都是左孩子的长度加上右孩子的长度，他存在一个覆盖问题  
        a[i].len=a[i].mr-a[i].ml;  
    }else if(a[i].r-a[i].l==1){  
        a[i].len=0;  
    }else{  
        a[i].len=a[i*2].len+a[i*2+1].len;  
    }  
    return ;  
}  
void updata(int i,Node b){  
    if(a[i].ml==b.y1&&a[i].mr==b.y2){  
        a[i].s+=b.flag;  
        callen(i);  
        return ;  
    }  
    if(b.y2<=a[i*2].mr) updata(i*2,b);  
    else if(b.y1>=a[i*2+1].ml) updata(i*2+1,b);  
    else{  
        Node temp=b;  
        temp.y2=a[i*2].mr;  
        updata(i*2,temp);  
        temp=b;  
        temp.y1=a[i*2+1].ml;  
        updata(i*2+1,temp);  
    }  
    callen(i);  
    return ;  
}  
int main(){  
    int n,t,p=1,te;  
    double x1,x2,y1,y2;  
    while(scanf("%d",&n),n){  
            t=1;  
        for(int i=0;i<n;i++){  
            scanf("%lf%lf%lf%lf",&x1,&y1,&x2,&y2);  
            node[t].x=x1;  
            node[t].y1=y1;  
            node[t].y2=y2;  
            node[t].flag=1;//入边  
            y[t++]=y1;  
            node[t].x=x2;  
            node[t].y1=y1;  
            node[t].y2=y2;  
            node[t].flag=-1;//出边  
            y[t++]=y2;  
        }  
        sort(node+1,node+t,cmp);  
        sort(y+1,y+t);  
        build(1,1,t-1);  
        updata(1,node[1]);  
        double sum=0;  
        for(int i=2;i<t;i++){  
            sum+=a[1].len*(node[i].x-node[i-1].x);  
            updata(1,node[i]);  
        }  
        printf("Test case #%d\n",p++);  
        printf("Total explored area: %.2lf\n\n",sum);  
    }  
    return 0;  
}