USACO 5.3 Window Area

Window Area
IV Balkan Olympiad

You've just be assigned the project of implemented a windowing interface. This windowing interface is fairly simple, and fortunately, you don't have to display the actual windows. There are 5 basic operations:

  1. Create a window
  2. Bring a window to the top
  3. Put a window to the bottom
  4. Destroy a window
  5. Output what percentage of a window is visible (i.e., isn't covered by windows above it).

In the input, the operations appear in the following format:

  • Create window: w(I,x,y,X,Y)
  • Bring window to top: t(I)
  • Put window on bottom: b(I)
  • Destroy window: d(I)
  • Output percentage visible: s(I)

The I is a unique identifier for each window, which is one character. The character can be any of 'a'..'z', 'A'..'Z', and '0'..'9'. No extra spaces will appear in the input.

(x,y) and (X,Y) are opposite corners of the window. When a window is created, it is put `on top'. You can't create a window with an identifier that is already in use, but you can destroy a window and then create a new one with the identifier of the destroyed window. Coordinates will be positive integers, and all windows will be of non-zero area (x != X and y != Y). The x and y coordinates are between 1 and 32767 inclusive.

PROGRAM NAME: window

INPUT FORMAT

The input file consists of a sequence of commands to your interpreter. They will be listed one per line. Terminate the program when no more input is available

SAMPLE INPUT (file window.in)

w(a,10,132,20,12)
w(b,8,76,124,15)
s(a)

OUTPUT FORMAT

Output lines only for the s() commands. Of course, there might be several s() commands (but no more than 500) so the output should be a sequence of percentages, one per line, stating the percentage of the windows that are visible. The percentages should be rounded to 3 decimal places.

SAMPLE OUTPUT (file window.out)

49.167

 ——————————————————————————————题解

借用USACO的字符画一下

 

*----------------*
|                |
|                |
|                |
|     *----*     |
|     |    |     |
|     |    |     | 
|     |    |     |
|     *----*     |
|                |
|                |
*----------------*
        ||
        \/
*-----*----*-----*
|     |    |     |
|     | 2  |     |
|     |    |     |
|     *----*     |
|     |    |     | 
|  1  |    |  3  | 
|     |    |     | 
|     *----*     |  
|     |  4 |     |   
|     |    |     |
*-----*----*-----*

       *-----*
       |   2 |
       |     |
*------------------*
|                  |  
|                  |
*------------------*
       |   4 |
       |     |
       *-----*

        *------------*
        |            |
*-------|            |
|       |            | 
|       |            |
|   1   *------------*
|       | 4 |
*-------*---*

这样上下左右的切割，递归处理
前四个操作只要记录一下高度值，修改高度就可以了
  1 /*
  2 ID: ivorysi
  3 LANG: C++
  4 PROG: window
  5 */
  6 #include <iostream>
  7 #include <cstdio>
  8 #include <cstring>
  9 #include <algorithm>
 10 #include <queue>
 11 #include <set>
 12 #include <vector>
 13 #include <string.h>
 14 #include <cmath>
 15 #define siji(i,x,y) for(int i=(x);i<=(y);++i)
 16 #define gongzi(j,x,y) for(int j=(x);j>=(y);--j)
 17 #define xiaosiji(i,x,y) for(int i=(x);i<(y);++i)
 18 #define sigongzi(j,x,y) for(int j=(x);j>(y);--j)
 19 #define inf 0x3f3f3f3f
 20 #define ivorysi
 21 #define mo 97797977
 22 #define hash 974711
 23 #define base 47
 24 #define pss pair<string,string>
 25 #define MAXN 5000
 26 #define fi first
 27 #define se second
 28 #define pii pair<int,int>
 29 #define esp 1e-8
 30 typedef long long ll;
 31 using namespace std;
 32 char a[50];
 33 int f,cut[205];
 34 int cnt;
 35 struct data{
 36     int lx,ly,rx,ry;
 37     int h;
 38 }window[205];
 39 int calc(char c) {
 40     if(c>='a' && c<='z') return c-'a'+1;
 41     else if (c>='A' && c<='Z') return c-'A'+27;
 42     else if(c>='0' && c<='9') return c-'0'+53;
 43 }
 44 void ins(int x,int y,int X,int Y,char c) {
 45     int t=calc(c);
 46     ++cnt;
 47     window[t].lx=min(x,X);
 48     window[t].ly=min(y,Y);
 49     window[t].rx=max(x,X);
 50     window[t].ry=max(y,Y);
 51     window[t].h=1;
 52     siji(i,1,62) {//这里原来打成xiaosiji忘改了
 53         if(window[i].h!=0 && i!=t) ++window[i].h;
 54     }
 55 }
 56 void top(char c) {
 57     int t=calc(c);
 58     int he=window[t].h;
 59     window[t].h=1;
 60     siji(i,1,62) {
 61         if(window[i].h!=0 && window[i].h<he && i!=t) ++window[i].h;
 62     }
 63 }
 64 void del(char c) {
 65     int t=calc(c);
 66     int he=window[t].h;
 67     window[t].h=0;
 68     siji(i,1,62) {
 69         if(window[i].h!=0 && window[i].h>he) --window[i].h;
 70     }
 71 }
 72 void bottom(char c) {
 73     int t=calc(c);
 74     int he=window[t].h;
 75     window[t].h=cnt;
 76     siji(i,1,62) {
 77         if(window[i].h!=0 && window[i].h>he && i!=t) --window[i].h;
 78     }
 79 }
 80 int solute(int k,int x1,int y1,int x2,int y2) {
 81     if(x2<=x1 || y2<=y1) return 0;
 82     int t=k;
 83     while(t>0&&(window[cut[t]].rx <=x1 || window[cut[t]].ry<=y1
 84         || window[cut[t]].lx>=x2 || window[cut[t]].ly>=y2)) --t;
 85     if(t<=0) return (x2-x1)*(y2-y1);
 86     
 87     int res=0;
 88     if(window[cut[t]].lx>x1) {
 89         res+=solute(t-1,x1,y1,window[cut[t]].lx,y2);
 90     }
 91     if(window[cut[t]].ly>y1) {
 92         res+=solute(t-1,max(x1,window[cut[t]].lx),y1,min(x2,window[cut[t]].rx),window[cut[t]].ly);
 93     }
 94     if(window[cut[t]].rx<x2) {
 95         res+=solute(t-1,window[cut[t]].rx,y1,x2,y2);
 96     }
 97     if(window[cut[t]].ry<y2) {
 98         res+=solute(t-1,max(x1,window[cut[t]].lx),window[cut[t]].ry,min(x2,window[cut[t]].rx),y2);
 99     }
100     return res;
101 }
102 void solve() {
103     int x1,y1,x2,y2;
104     while(scanf("%s",a+1)!=EOF) {
105         if(a[1]=='w') {
106             siji(i,4,strlen(a+1)) {
107                 if(a[i]<'0' || a[i] > '9') a[i]=' ';
108             }
109             sscanf(a+4,"%d%d%d%d",&x1,&y1,&x2,&y2);
110             ins(x1,y1,x2,y2,a[3]);
111         }
112         else if(a[1]=='t') {
113             top(a[3]);
114         }
115         else if(a[1]=='b') {
116             bottom(a[3]);
117         }
118         else if(a[1]=='d') {
119             del(a[3]);
120         }
121         else {
122             f=0;
123             int t=calc(a[3]);
124             if(window[t].h==0) {puts("0.000");continue;}
125             
126             siji(i,1,62) {
127                 if(window[t].h>window[i].h && window[i].h!=0) cut[++f]=i;
128             }
129             int sa=solute(f,window[t].lx,window[t].ly,window[t].rx,window[t].ry);
130             int sb=(window[t].ry-window[t].ly)*(window[t].rx-window[t].lx);
131             printf("%.3lf\n",(double)sa/sb*100);
132         }
133     }
134 }
135 int main(int argc, char const *argv[])
136 {
137 #ifdef ivorysi
138     freopen("window.in","r",stdin);
139     freopen("window.out","w",stdout);
140 #else
141     freopen("f1.in","r",stdin);
142 #endif
143     solve();
144     return 0;
145 }

 

 

 

posted @ 2017-02-14 16:55  sigongzi  阅读(270)  评论(0)  编辑  收藏  举报