HNOI2002 营业额统计 平衡查找树

 1 // File Name: first.cpp
 2 // Author: darkdream
 3 // Created Time: 2014年07月15日 星期二 19时41分13秒
 4 
 5 #include<vector>
 6 #include<list>
 7 #include<map>
 8 #include<set>
 9 #include<deque>
10 #include<stack>
11 #include<bitset>
12 #include<algorithm>
13 #include<functional>
14 #include<numeric>
15 #include<utility>
16 #include<sstream>
17 #include<iostream>
18 #include<iomanip>
19 #include<cstdio>
20 #include<cmath>
21 #include<cstdlib>
22 #include<cstring>
23 #include<ctime>
24 #include<climits>
25 #include<queue>
26 
27 using namespace std;
28 
29 int main(){
30 
31     long long n ; 
32     while(scanf("%lld",&n) != EOF)
33     {
34       long long x; 
35       set<long long>a;
36       set<long long>::iterator l,en,be;
37       set<long long>::iterator r;
38       long long sum = 0 ;
39       scanf("%lld",&x);
40       sum += x;
41       a.insert(x);
42       for(int i = 2;i <= n;i ++)
43       {
44           scanf("%lld",&x);
45           if(a.find(x) != a.end()) continue;
46           
47           a.insert(x);
48           en = a.end();
49           --en;
50           if(a.find(x) == en)
51           {
52              l = a.find(x);
53               --l ; 
54         //     printf("**%lld\n",*l);
55              sum += x - *l;
56           }else if(a.find(x) == a.begin()){
57               l = a.find(x);
58               ++l  ; 
59               sum += *l -x;
60         //      printf("**%lld\n",*l);
61           }else {
62               l = a.find(x);
63               r = a.find(x);
64               r = ++r;
65               l = --l;
66         //      printf("**%lld %lld\n",*l,*r);
67               sum += min(x-*l,*r-x);
68           }
69 
70       }
71       printf("%lld\n",sum);
72     }
73     
74     return 0;
75 }