Stall Reservations POJ 3190(贪心)

 1 #include <iostream>
 2 #include <algorithm>
 3 #include <utility>
 4 #include <cstdio>
 5 #include <cmath>
 6 #include <cstring>
 7 #include <string>
 8 #include <vector>
 9 #include <stack>
10 #include <queue>
11 #include <map>
12 #include <set> 
13 
14 using namespace std;
15 typedef long long LL;
16 const int INF_INT=0x3f3f3f3f;
17 const LL INF_LL=0x3f3f3f3f3f3f3f3f; 
18 typedef pair<int,int> P;
19 
20 struct G
21 {
22     int first,second,order;
23 }interval[50000];
24 int used[50000];
25 
26 bool cmp(G a,G b)
27 {
28     return a.first<b.first;
29 }
30 
31 int main()
32 {
33 //    freoGen("black.in","r",stdin);
34 //    freopen("black.out","w",stdout);
35     int n;
36     cin>>n;
37     for(int i=0;i<n;i++) scanf("%d %d",&interval[i].first,&interval[i].second),interval[i].order=i;
38     sort(interval,interval+n,cmp);
39     priority_queue<P,vector<P>,greater<P> > que;
40     int i=0,now=0,ans=0,cnt=0;
41     while(i<n)
42     {
43         que.push(P(interval[i].second,interval[i].order));
44         now=interval[i].first;
45         cnt++;
46         if(que.top().first<now) used[interval[i].order]=used[que.top().second],que.pop(),cnt--;
47         else used[interval[i].order]=cnt;
48         ans=max(cnt,ans);
49         i++;
50     }
51     printf("%d\n",ans);
52     for(int i=0;i<n;i++) printf("%d\n",used[i]);
53     return 0;
54 }