hdu 1556 Color the ball

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思路; 树状数组

分析:

1 简单的区间更新，单点查询问题

代码:

/***********************************************
* By: chenguolin                               * 
* Date: 2013-08-20                             *
* Address: http://blog.csdn.net/chenguolinblog *
***********************************************/
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;

const int MAXN = 100010;

int n;
int treeNum[MAXN];

int lowbit(int x){
    return x&(-x);
}

int getSum(int x){
    int sum = 0;
    while(x){
        sum += treeNum[x];
        x -= lowbit(x);
    }
    return sum;
}

void add(int x , int val){
    while(x < MAXN){
         treeNum[x] += val;
         x += lowbit(x);
    }
}

void solve(){
    int x , y , m;
    memset(treeNum , 0 , sizeof(treeNum));
    m = n;
    while(m--){
        scanf("%d%d" , &x , &y);
        add(x , 1);
        add(y+1 , -1);
    }
    printf("%d" , getSum(1));
    for(int i = 2 ; i <= n ; i++)
        printf(" %d" , getSum(i));
    puts("");
}

int main(){
    while(scanf("%d" , &n) && n)
         solve();
    return 0;
}