POJ(2481)Cows 树状数组

#include <iostream>
#include <stdio.h>
#include <string>
#include <string.h>
#include <algorithm>
#include <math.h>
#include <fstream>
#include <vector>
#include <map>
#include <queue>
#include <stack>
#include <math.h>
#include <stdlib.h>
using namespace std ;
const int maxn = 100005;
int n;
struct cow{
int id;
int l,r;
friend bool operator<(const cow &a,const cow &b){
if(a.r == b.r)
return a.l < b.l;
return a.r > b.r;
}
}cow[maxn];
int c[maxn];
int lowbit(int x){
return x&(-x);
}
void update(int id,int val,int up){
for(int i = id;i <= up;i+=lowbit(i))
c[i] += val;
}
int query(int id){
int ans = 0;
for(int i = id;i > 0;i-=lowbit(i))
ans += c[i];
return ans;
}
int out[maxn];
int main(){
while(scanf("%d",&n)&&n){
int up = -1;
for(int i = 1;i <= n;i++){
scanf("%d%d",&cow[i].l,&cow[i].r);
cow[i].l++;
cow[i].r++;
cow[i].id = i;
if(up < cow[i].l)
up = cow[i].l;
}
sort(cow+1,cow+n+1);
//for(int i = 1;i <= n;i++)
//  printf("%d %d\n",cow[i].l,cow[i].r);
memset(c,0,sizeof(c)) ;
out[cow[1].id]=0;
update(cow[1].l,1,up);
for(int i = 2;i <= n;i++){
if(cow[i].l == cow[i-1].l && cow[i].r == cow[i-1].r)
out[cow[i].id] = out[cow[i-1].id];
else
out[cow[i].id] = query(cow[i].l);
update(cow[i].l,1,up);
}
printf("%d",out[1]) ;
for(int i = 2;i <= n;i++)
printf(" %d",out[i]);
printf("\n");
}
return 0 ;
}