hdu 1556 Color the ball （树状数组）

Color the ball
Time Limit: 9000/3000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 28423    Accepted Submission(s): 13858

Problem Description
N个气球排成一排，从左到右依次编号为1,2,3....N.每次给定2个整数a b(a <= b),lele便为骑上他的“小飞鸽"牌电动车从气球a开始到气球b依次给每个气球涂一次颜色。但是N次以后lele已经忘记了第I个气球已经涂过几次颜色了，你能帮他算出每个气球被涂过几次颜色吗？
 

Input
每个测试实例第一行为一个整数N,(N <= 100000).接下来的N行，每行包括2个整数a b(1 <= a <= b <= N)。
当N = 0，输入结束。
 

Output
每个测试实例输出一行，包括N个整数，第I个数代表第I个气球总共被涂色的次数。
 

Sample Input
3
1 1
2 2
3 3
3
1 1
1 2
1 3
0
 

Sample Output
1 1 1
3 2 1

引至：help

C/C++:

#include <map>
#include <queue>
#include <cmath>
#include <vector>
#include <string>
#include <cstdio>
#include <cstring>
#include <climits>
#include <iostream>
#include <algorithm>
#define INF 0x3f3f3f3f
using namespace std;
const int MAXN = 1e5 + 10;
int n, c[MAXN], a, b;

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

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

int sum(int x)
{
    int sum = 0;
    while (x >= 1)
    {
        sum += c[x];
        x -= lowbit(x);
    }
    return sum;
}

int main()
{
    while (scanf("%d", &n), n)
    {
        memset(c, 0, sizeof(c));
        for (int i = 1; i <= n; ++ i)
        {
            scanf("%d%d", &a, &b);
            add(a, 1);
            add(b + 1, -1);
        }
        for (int i = 1; i < n; ++ i)
            printf("%d ", sum(i));
        printf("%d\n", sum(n));
    }
}