POJ Training Plan 1177_Picture (scanned line/line segment tree + discrete)

POJ Training Plan 1177_Picture (scanned line/line segment tree + discrete)

Solution report

Question:

Returns the length of the rectangle.

Ideas:

Scanned on the left.

# Include
 
  
# Include
  
   
# Include
   
    
# Include
    
     
Using namespace std; struct Seg {int lx, rx, ly, ry, h, v; friend bool operator <(Seg a, Seg B) {return a. h
     
      
R | qr
      
        > 1; update1 (rt <1, l, mid, ql, qr, v); update1 (rt <1 | 1, mid + 1, r, ql, qr, v); push_up1 (rt, l, r);} void push_up2 (int rt, int l, int r) {if (lz [rt]) {sum [rt] = _ hy [r + 1]-_ hy [l];} else sum [rt] = sum [rt <1] + sum [rt <1 | 1];} void update2 (int rt, int l, int r, int ql, int qr, int v) {if (ql> r | qr
       
         > 1; update2 (rt <1, l, mid, ql, qr, v); update2 (rt <1 | 1, mid + 1, r, ql, qr, v); push_up2 (rt, l, r);} int main () {int lx, rx, ly, ry, n, I, j; scanf ("% d ", & n); for (I = 0; I
        
         

         
Picture
         
 

          
  
 
   
 
    
Time Limit:2000 MS
 
    
 
 
    
Memory Limit:10000 K
 
   
 
   
 
    
Total Submissions:10332
 
    
 
 
    
Accepted:5485
 
   
 
  
         
 
         

         
Description
A number of rectangular posters, photographs and other pictures of the same shape are pasted on a wall. their sides are all vertical or horizontal. each rectangle can be partially or totally covered by the others. the length of the boundary of the union of all rectangles is called the perimeter.
         

         
Write a program to calculate the perimeter. An example with 7 rectangles is shown in Figure 1.
         

         
         
The cZ operator? Http://www.bkjia.com/kf/ware/vc/ "target =" _ blank "class =" keylink "> memory + CjxjZW50ZXI + pgltzybzcm9" http://www.2cto.com/uploadfile/Collfiles/20140813/20140813085758254.jpg "alt =" \ ">
         
The vertices of all rectangles have integer coordinates.
         

         
Input
Your program is to read from standard input. the first line contains the number of rectangles pasted on the wall. in each of the subsequent lines, one can find the integer coordinates of the lower left vertex and the upper right vertex of each rectangle. the values of those coordinates are given as ordered pairs consisting of an x-coordinate followed by a y-coordinate.
         

         
0 <= number of rectangles <5000
         
All coordinates are in the range [-keys, 10000] and any existing rectangle has a positive area.
         
Output
Your program is to write to standard output. The output must contain a single line with a non-negative integer which corresponds to the perimeter for the input rectangles.
         
Sample Input
         
7-15 0 5 10-5 8 20 2515 -4 24 140 -6 16 42 15 10 2230 10 36 2034 0 40 16
         
Sample Output
         
228
         
Source
IOI 1998