#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;

#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1

const int maxn=11000;

int flag[maxn*10]; double sum[maxn*10];
double X[maxn];

struct Line
{
    double xl,xr,y;
    int s;

    bool operator<(const Line &M) const
    {
        return y<M.y;
    }

}line[maxn];

void push_up(int l,int r,int rt)
{
    if(flag[rt]) sum[rt]=X[r+1]-X[l];
    else if(l==r) sum[rt]=0;
    else sum[rt]=sum[rt<<1]+sum[rt<<1|1];
}

void update(int l,int r,int rt,int L,int R,int c)
{
    if(L<=l&&r<=R)
    {
        flag[rt]+=c;
        push_up(l,r,rt);
        return ;
    }

    int m=(l+r)>>1;

    if(R<=m) update(lson,L,R,c);
    else if(L>m) update(rson,L,R,c);
    else
    {
        update(lson,L,m,c);
        update(rson,m+1,R,c);
    }

    push_up(l,r,rt);
}

int find(double x,int k)
{
    int low=1,high=k,mid;
    while(low<=high)
    {
        mid=(low+high)/2;
        if(X[mid]==x) return mid;
        else if(X[mid]>x) high=mid-1;
        else low=mid+1;
    }
}

int main()
{
    int n,cas=1;
while(scanf("%d",&n)!=EOF&&n)
{
    memset(flag,0,sizeof(flag));
    memset(sum,0,sizeof(sum));

    int num=0;
    for(int i=0;i<n;i++)
    {
        double x1,x2,y1,y2;
        scanf("%lf%lf%lf%lf",&x1,&y1,&x2,&y2);
        line[++num]=(Line){x1,x2,y1,1};
        X[num]=x1;
        line[++num]=(Line){x1,x2,y2,-1};
        X[num]=x2;
    }

    sort(X+1,X+1+num);
    sort(line+1,line+1+num);

    int k=1;
    for(int i=2;i<=num;i++)
    {
        if(X[i]!=X[i-1]) X[++k]=X[i];
    }
    double ans=0;
    for(int i=1;i<num;i++)
    {
        int l=find(line[i].xl,k);
        int r=find(line[i].xr,k)-1;
        update(1,k,1,l,r,line[i].s);
        ans+=sum[1]*(line[i+1].y-line[i].y);
    }

    printf("Test case #%d\n",cas++);
    printf("Total explored area: %.2lf\n\n",ans);
}
    return 0;
}