POJ-2481 Cows(树状数组)

 1 #include <cstdio>
 2 #include <cmath>
 3 #include <cstring>
 4 #include <cstdlib>
 5 #include <queue>
 6 #include <stack>
 7 #include <vector>
 8 #include <iostream>
 9 #include "algorithm"
10 using namespace std;
11 typedef long long LL;
12 const int MAX=100005;
13 int n;
14 int sum[MAX];
15 int ans[MAX];
16 struct Seg{
17     int a,b,c;
18 }seg[MAX];
19 void add(int x,int y){
20     for (;x<=n;sum[x]+=y,x+=(x&-x));
21 }
22 int search(int x){
23     int an(0);
24     for (;x>0;an+=sum[x],x-=(x&-x));
25     return an;
26 }
27 bool cmp(Seg x,Seg y){
28     if (x.b!=y.b)
29      return x.b>y.b;
30     else
31      return x.a<y.a;
32 }
33 int main(){
34     freopen ("cows.in","r",stdin);
35     freopen ("cows.out","w",stdout);
36     int i,j;
37     while (1)
38     {scanf("%d",&n);
39      if (n==0)
40       break;
41      for (i=1;i<=n;i++)
42      {scanf("%d%d",&seg[i].a,&seg[i].b);
43       seg[i].c=i;
44      }
45      sort(seg+1,seg+n+1,cmp);
46      memset(sum,0,sizeof(sum));
47      memset(ans,0,sizeof(ans));
48      for (i=1;i<=n;i++)
49      {if (i!=1 && seg[i].a==seg[i-1].a && seg[i].b==seg[i-1].b)
50        ans[seg[i].c]=ans[seg[i-1].c];
51       else
52        ans[seg[i].c]=search(seg[i].a+1);
53       add(seg[i].a+1,1);
54      }
55      for (i=1;i<n;i++)
56       printf("%d ",ans[i]);
57      printf("%d\n",ans[n]);
58     }
59     return 0;
60 }