hdu 4638 Group

理解题意：连续的数分为一组，每次判断下就可以了！！

代码如下：

 

 1 #include<iostream>
 2 #include<stdio.h>
 3 #include<algorithm>
 4 #include<iomanip>
 5 #include<cmath>
 6 #include<cstring>
 7 #include<vector>
 8 #define ll __int64
 9 #define pi acos(-1.0)
10 #define MAX 100105
11 using namespace std;
12 int R,L,an[MAX],ans[MAX],res;
13 bool vis[MAX];
14 struct node
15 {
16     int x,y,l,p;
17 }q[MAX];
18 bool cmp(const node &a,const node &b)
19 {
20     if(a.l==b.l) return a.y<b.y;
21     return a.l<b.l;
22 }
23 void query(int x,int y,int flag)
24 {
25     if(flag){
26         for(int i=x;i<L;i++){
27             vis[an[i]]=1;
28             if(vis[an[i]-1]&&vis[an[i]+1]) res--;
29             else if(!vis[an[i]-1]&&!vis[an[i]+1]) res++;
30         }
31         for(int i=R+1;i<=y;i++){
32             vis[an[i]]=1;
33             if(vis[an[i]-1]&&vis[an[i]+1]) res--;
34             else if(!vis[an[i]-1]&&!vis[an[i]+1]) res++;
35         }
36         for(int i=L;i<x;i++){
37             vis[an[i]]=0;
38             if(vis[an[i]-1]&&vis[an[i]+1]) res++;
39             else if(!vis[an[i]-1]&&!vis[an[i]+1]) res--;
40         }
41         for(int i=y+1;i<=R;i++){
42             vis[an[i]]=0;
43             if(vis[an[i]-1]&&vis[an[i]+1]) res++;
44             else if(!vis[an[i]-1]&&!vis[an[i]+1]) res--;
45         }
46     }
47     else{
48         for(int i=x;i<=y;i++){
49             vis[an[i]]=1;
50             if(vis[an[i]-1]&&vis[an[i]+1]) res--;
51             else if(!vis[an[i]-1]&&!vis[an[i]+1]) res++;
52         }
53     }
54     L=x;R=y;
55 }
56 int main(){
57     int n,t,i,j,m,c;
58     scanf("%d",&c);
59     while(c--){
60         scanf("%d%d",&n,&t);
61         for(i=1;i<=n;i++) scanf("%d",&an[i]);
62         m=sqrt(1.0*n);
63         for(i=0;i<t;i++){
64             scanf("%d%d",&q[i].x,&q[i].y);
65             q[i].l=q[i].x/m;
66             q[i].p=i;
67         }
68         sort(q,q+t,cmp);
69         res=0;
70         memset(vis,0,sizeof(vis));
71         for(i=0;i<t;i++){
72             query(q[i].x,q[i].y,i);
73             ans[q[i].p]=res;
74         }
75         for(i=0;i<t;i++)
76             printf("%d\n",ans[i]);
77     }
78     return 0;
79 }
View Code

 

 

 

posted @ 2013-08-16 17:35  _随心所欲_  阅读(290)  评论(0)    收藏  举报