#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<set>
#include<map>
#include<vector>
#include<queue>
using namespace std;
#define ll long long
#define RG register
#define MAX 500
#define lson (now<<1)
#define rson (now<<1|1)
struct Node{double x1,x2,y,w;}p[MAX];
bool operator<(Node a,Node b){return a.y<b.y;}
double S[MAX];
int top;
int n,tot;
struct SegmentTreeNode
{
    double ss;
    int ly;
}t[MAX<<3];
void pushup(int now,int l,int r)
{
    if(t[now].ly)t[now].ss=S[r+1]-S[l];
    else if(l==r)t[now].ss=0;
    else t[now].ss=t[lson].ss+t[rson].ss;
}
void Modify(int now,int l,int r,int L,int R,int w)
{
    if(L<=l&&r<=R)
    {
        t[now].ly+=w;
        pushup(now,l,r);
        return;
    }
    int mid=(l+r)>>1;
    if(L<=mid)Modify(lson,l,mid,L,R,w);
    if(R>mid)Modify(rson,mid+1,r,L,R,w);
    pushup(now,l,r);
}
int main()
{
    int TT=0;
    while(scanf("%d",&n))
    {
        ++TT;
        if(!n)break;
        tot=top=0;
        double x1,x2,y1,y2;
        for(int i=1;i<=n;++i)
        {
            scanf("%lf%lf%lf%lf",&x1,&y1,&x2,&y2);
            p[++tot]=(Node){x1,x2,y1,1};
            p[++tot]=(Node){x1,x2,y2,-1};
            S[++top]=x1,S[++top]=x2;
        }
        sort(&S[1],&S[top+1]);
        sort(&p[1],&p[tot+1]);
        top=unique(&S[1],&S[top+1])-S-1;
        double ans=0;
        for(int i=1;i<tot;++i)
        {
            int l=lower_bound(&S[1],&S[top+1],p[i].x1)-S;
            int r=lower_bound(&S[1],&S[top+1],p[i].x2)-S-1;
            if(l<=r)Modify(1,1,top,l,r,p[i].w);
            if(i!=tot)ans+=(p[i+1].y-p[i].y)*t[1].ss;
        }
        printf("Test case #%d\nTotal explored area: %.2f\n\n",TT,ans);
        memset(t,0,sizeof(t));
    }
    return 0;
}