poj1151

#include<cstdio>
#include<cstring>
#include<cmath>
#include<iostream>
#include<algorithm>
using namespace std;
const int N=101;
const double eps=1e-6; 
double ans=0,x[N<<1],y[N<<1],pos[N][4];
bool hash[N<<1][N<<1];
int cmp(const void *a,const void *b){
    double *aa=(double *)a;
    double *bb=(double *)b;
    if(fabs(*aa-*bb)<=eps) return 0;
    else if(*aa-*bb>0) return 1;
    return -1;
}
int main(){
    freopen("sh.txt","r",stdin);
    int i,j,k,n,x1,y1,x2,y2,cas=0;
    while(scanf("%d",&n)==1){
        if(!n) break;
        for(ans=k=i=0;i<n;i++,k+=2){
            scanf("%lf%lf%lf%lf",&pos[i][0],&pos[i][1],&pos[i][2],&pos[i][3]);
            x[k]=pos[i][0];y[k]=pos[i][1];x[k+1]=pos[i][2];y[k+1]=pos[i][3];
        }
        memset(hash,0,sizeof hash);
        qsort(x,n<<1,sizeof x[0],cmp);
        qsort(y,n<<1,sizeof y[0],cmp);
        for(i=0;i<n;i++){
            for(k=0;fabs(x[k]-pos[i][0])>eps;k++); x1=k;
            for(k=0;fabs(y[k]-pos[i][1])>eps;k++); y1=k;
            for(k=0;fabs(x[k]-pos[i][2])>eps;k++); x2=k;
            for(k=0;fabs(y[k]-pos[i][3])>eps;k++); y2=k;
            for(j=x1;j<x2;j++){
                for(k=y1;k<y2;k++){
                    hash[j][k]=1;
                }
            }        
        }
        for(i=0;i<2*n-1;i++){
            for(j=0;j<2*n-1;j++){
                ans+=hash[i][j]*(x[i+1]-x[i])*(y[j+1]-y[j]);
            }
        }
        printf("Test case #%d\n",++cas);
        printf("Total explored area: %.2lf\n\n",ans);
    }
    return 0;
}