解题报告

题意：

给定的矩形里面有镂空的矩阵，求矩阵面积并。

思路：

直接把一个图形拆成4个矩形，进行面积并。

扫描线+线段树

#include 
  
   
#include 
   
     #include 
    
      #include 
     
       #define LL __int64 using namespace std; struct Seg { int lx,rx,h,v; friend bool operator < (Seg a,Seg b) { return a.h
      
       r||qr
       
        >1; update(rt<<1,l,mid,ql,qr,v); update(rt<<1|1,mid+1,r,ql,qr,v); push_up(rt,l,r); } int main() { int n,i,j,x1,y1,x2,y2,x3,y3,x4,y4; while(~scanf("%d",&n)) { if(!n)break; int m=0; memset(lz,0,sizeof(lz)); memset(sum,0,sizeof(sum)); for(i=0; i
        
         
 
         
 
         
 Posters
 
         Time Limit: 5000/2000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
 Total Submission(s): 4585 Accepted Submission(s): 1029
 
         
 
         
 Problem Description Ted has a new house with a huge window. In this big summer, Ted decides to decorate the window with some posters to prevent the glare outside. All things that Ted can find are rectangle posters. 
         
 
         
 However, Ted is such a picky guy that in every poster he finds something ugly. So before he pastes a poster on the window, he cuts a rectangular hole on that poster to remove the ugly part. Ted is also a careless guy so that some of the pasted posters may overlap when he pastes them on the window. 
         
 
         
 Ted wants to know the total area of the window covered by posters. Now it is your job to figure it out.
         
 
         
 To make your job easier, we assume that the window is a rectangle located in a rectangular coordinate system. The window’s bottom-left corner is at position (0, 0) and top-right corner is at position (50000, 50000). The edges of the window, the edges of the posters and the edges of the holes on the posters are all parallel with the coordinate axes. 
         
 
         
 Input The input contains several test cases. For each test case, the first line contains a single integer N (0
          
          
 The input ends with a line of single zero.
          
 
          
 Output For each test case, output a single line with the total area of window covered by posters. 
          
 Sample Input 
          
2
0 0 10 10 1 1 9 9
2 2 8 8 3 3 7 7
0
 
          
 Sample Output 
          
56
 
          
 Source 2009 Asia Ningbo Regional Contest Hosted by NIT