HDU 3265 Posters

 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <cmath>
 5 #include <algorithm>
 6 #include <climits>
 7 #include <vector>
 8 #include <queue>
 9 #include <cstdlib>
10 #include <string>
11 #include <set>
12 #include <stack>
13 #define LL long long
14 #define pii pair<int,int>
15 #define INF 0x3f3f3f3f
16 using namespace std;
17 const int maxn = 100000;
18 struct node{
19     int lt,rt,cnt,len;
20 };
21 struct Line{
22     int lx,rx,h,delta;
23     Line(int x = 0,int y = 0,int z = 0,int d = 0){
24         lx = x;
25         rx = y;
26         h = z;
27         delta = d;
28     }
29     bool operator<(const Line &b) const{
30         return h < b.h;
31     }
32 };
33 node tree[maxn<<2];
34 Line line[maxn<<2];
35 int tot;
36 void build(int lt,int rt,int v){
37     tree[v].lt = lt;
38     tree[v].rt = rt;
39     tree[v].cnt = tree[v].len = 0;
40     if(lt + 1 == rt) return;
41     int mid = (lt + rt)>>1;
42     build(lt,mid,v<<1);
43     build(mid,rt,v<<1|1);
44 }
45 void pushup(int v){
46     if(tree[v].cnt) tree[v].len = tree[v].rt - tree[v].lt;
47     else if(tree[v].lt + 1 == tree[v].rt) tree[v].len = 0;
48     else tree[v].len = tree[v<<1].len + tree[v<<1|1].len;
49 }
50 void update(int lt,int rt,int v,int delta){
51     if(tree[v].lt >= lt && tree[v].rt <= rt){
52         tree[v].cnt += delta;
53         pushup(v);
54         return;
55     }
56     if(lt < tree[v<<1].rt) update(lt,rt,v<<1,delta);
57     if(rt > tree[v<<1|1].lt) update(lt,rt,v<<1|1,delta);
58     pushup(v);
59 }
60 int main() {
61     int n,x1,y1,x2,y2,x3,y3,x4,y4;
62     while(scanf("%d",&n),n){
63         build(0,50010,1);
64         for(int i = tot = 0; i < n; ++i){
65             scanf("%d %d %d %d",&x1,&y1,&x2,&y2);
66             scanf("%d %d %d %d",&x3,&y3,&x4,&y4);
67             line[tot++] = Line(x1,x4,y4,1);
68             line[tot++] = Line(x1,x4,y2,-1);
69             line[tot++] = Line(x4,x2,y3,1);
70             line[tot++] = Line(x4,x2,y2,-1);
71             line[tot++] = Line(x3,x2,y1,1);
72             line[tot++] = Line(x3,x2,y3,-1);
73             line[tot++] = Line(x1,x3,y1,1);
74             line[tot++] = Line(x1,x3,y4,-1);
75         }
76         sort(line,line+tot);
77         LL sum = 0;
78         for(int i = 0; i+1 < tot; ++i){
79             update(line[i].lx,line[i].rx,1,line[i].delta);
80             sum += (LL)tree[1].len*(line[i+1].h - line[i].h);//这个地方有点坑啊。。注意溢出。。
81         }
82         cout<<sum<<endl;
83     }
84     return 0;
85 }