hdu 题目1556 Color the ball（线段树）

 

 

Color the ball

Time Limit: 9000/3000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 5853    Accepted Submission(s): 3117

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

 

 

#define N 400000
#include <iostream>
#include <stdio.h>

using namespace std;

typedef struct interval_tree
{
    int lside,rside,cnt;
}interval_tree;

interval_tree tree[N];

int Pnt[N],k;

void build_tree(int l,int r,int i)
{
    
        tree[i].lside = l;
        tree[i].rside = r;
        tree[i].cnt = 0;
        if(l==r) return;
        int mid = (tree[i].rside+tree[i].lside)/2;
        build_tree(l,mid,2*i);
        build_tree(mid+1,r,2*i+1);    
}

void count(int i)
{
	if(tree[i].lside == tree[i].rside)  
   {
		Pnt[k++] = tree[i].cnt;	
		return;
	}
	tree[i*2].cnt += tree[i].cnt;
	tree[i*2+1].cnt += tree[i].cnt;
	count(2*i);
	count(2*i+1);
}


void change(int a,int b,int i)
{
	 if(a<=tree[i].lside && b>=tree[i].rside)  
    {    
        tree[i].cnt++;
        return;
    }
    int mid =(tree[i].lside+tree[i].rside)/2;
    if(b <= mid )     change(a,b,2*i);
    else if(a > mid )    change(a,b,2*i+1);
    else 
    {
        change(a,mid,2*i);
        change(mid+1,b,2*i+1);
    }
}
int main()
{
    int i,n,a,b;
    while(scanf("%d",&n),n)
    {

        build_tree(1,n,1);
        while(n--)
        {
            scanf("%d%d",&a,&b);
            change(a,b,1);
        }
        k=0;
        count(1);
        for(i=0;i<k-1;i++)
        	printf("%d ",Pnt[i]);
        printf("%d\n",Pnt[k-1]);
    }
    return 0;
}