hdu1698Just a Hook（线段树区间覆盖)

http://acm.hdu.edu.cn/showproblem.php?pid=1698

View Code 
 1 #include <iostream>
 2 #include<cstdio>
 3 #include<string.h>
 4 using namespace std;
 5 #define max 100000
 6 int s[max*4],te[max*4];
 7 void pushup(int w)
 8 {
 9     s[w] = s[2*w]+s[2*w+1];
10 }
11 void pushdown(int w,int m)
12 {
13     if(te[w])
14     {
15         te[2*w] = te[2*w+1] = te[w];
16         s[2*w] = (m-m/2)*te[w];
17         s[2*w+1] = te[w]*(m/2);
18         te[w] =0;
19     }
20 }
21 void build(int l,int r,int w)
22 {
23     te[w] = 0;
24     if(l==r)
25     {
26         s[w] = 1;
27         return ;
28     }
29     int m = (l+r)/2;
30     build(l,m,2*w);
31     build(m+1,r,2*w+1);
32     pushup(w);
33 }
34 void update(int a,int b,int c,int l,int r,int w)
35 {
36     if(a<=l&&b>=r)
37     {
38         te[w] = c;
39         s[w]=c*(r-l+1);
40         return ;
41     }
42     pushdown(w,r-l+1);
43     int m = (l+r)/2;
44     if(a<=m)
45     update(a,b,c,l,m,2*w);
46     if(b>m)
47     update(a,b,c,m+1,r,2*w+1);
48     pushup(w);
49 }
50 int main()
51 {
52     int i,j,k =0 ,t,n,m,a,b,c;
53     scanf("%d",&t);
54     while(t--)
55     {
56         k++;
57         scanf("%d",&n);
58         build(1,n,1);
59         scanf("%d",&m);
60         while(m--)
61         {
62             scanf("%d%d%d",&a,&b,&c);
63             update(a,b,c,1,n,1);
64         }
65         printf("Case %d: The total value of the hook is ",k);
66         printf("%d.\n",s[1]);
67     }
68     return 0;
69 }

 

posted @ 2012-08-09 23:40  _雨  阅读(171)  评论(0)  编辑  收藏  举报