HDU 5023 A Corrupt Mayor's Performance Art(线段树区间更新)

A Corrupt Mayor's Performance Art

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 100000/100000 K (Java/Others) Total Submission(s): 1545    Accepted Submission(s): 537

Problem Description

   Corrupt governors always find ways to get dirty money.  Paint something, then sell the worthless painting at a high price to someone who wants to bribe him/her on an auction, this seemed a safe way for mayor X to make money.
   Because a lot of people praised mayor X's painting(of course, X was a mayor), mayor X believed more and more that he was a very talented painter. Soon mayor X was not satisfied with only making money. He wanted to be a famous painter. So he joined the local painting associates. Other painters had to elect him as the chairman of the associates. Then his painting sold at better price.
   The local middle school from which mayor X graduated, wanted to beat mayor X's horse fart(In Chinese English, beating one's horse fart means flattering one hard). They built a wall, and invited mayor X to paint on it. Mayor X was very happy. But he really had no idea about what to paint because he could only paint very abstract paintings which nobody really understand. Mayor X's secretary suggested that he could make this thing not only a painting, but also a performance art work.
   This was the secretary's idea:
   The wall was divided into N segments and the width of each segment was one cun(cun is a Chinese length unit). All segments were numbered from 1 to N, from left to right. There were 30 kinds of colors mayor X could use to paint the wall. They named those colors as color 1, color 2 .... color 30. The wall's original color was color 2. Every time mayor X would paint some consecutive segments with a certain kind of color, and he did this for many times. Trying to make his performance art fancy, mayor X declared that at any moment, if someone asked how many kind of colors were there on any consecutive segments, he could give the number immediately without counting.
   But mayor X didn't know how to give the right answer. Your friend, Mr. W was an secret officer of anti-corruption bureau, he helped mayor X on this problem and gained his trust. Do you know how Mr. Q did this?

 

Input

   There are several test cases.
   For each test case:
   The first line contains two integers, N and M ,meaning that the wall is divided into N segments and there are M operations(0 < N <= 1,000,000; 0<M<=100,000)
   Then M lines follow, each representing an operation. There are two kinds of operations, as described below:
   1)  P a b c    a, b and c are integers. This operation means that mayor X painted all segments from segment a to segment b with color c ( 0 < a<=b <= N, 0 < c <= 30).
   2)  Q a b    a and b are integers. This is a query operation. It means that someone asked that how many kinds of colors were there from segment a to segment b ( 0 < a<=b <= N).
   Please note that the operations are given in time sequence.
   The input ends with M = 0 and N = 0.

 

Output

For each query operation, print all kinds of color on the queried segments. For color 1, print 1, for color 2, print 2 ... etc. And this color sequence must be in ascending order.

 

Sample Input

5 10 P 1 2 3 P 2 3 4 Q 2 3 Q 1 3 P 3 5 4 P 1 2 7 Q 1 3 Q 3 4 P 5 5 8 Q 1 5 0 0

 

Sample Output

4 3 4 4 7 4 4 7 8

题目大意：

　　就是说，给你一个长度为n的区间，然后给每个区间的初始颜色都是2，现在有m个操作，有给这个区间染色的，有查询这个区间颜色种类的，求出某个区间中共有多少种颜色？

解题思路：

　　nlogn的时间建立一颗所有节点都是颜色2的线段树。然后，根据我们每次的询问操作，记录下涵盖在某个节点所包围的区间里面的颜色的种类，然后，每次输出的时候，排个序就行了。

代码：

# include<cstdio>
# include<iostream>
# include<cstring>
# include<algorithm>

using namespace std;

# define MAX 1000004
# define lid id<<1
# define rid id<<1|1

struct Segtree
{
    int l,r;
    int color;
}tree[MAX*4];
int num[233];
int tot;



void build( int id,int l,int r )
{
    tree[id].l = l; tree[id].r = r;
    tree[id].color = 2;
    if ( l==r )
    {
        return;
    }
    int mid = ( tree[id].l+tree[id].r )/2;
    build(lid,l,mid);
    build(rid,mid+1,r);
    //push_up(id);
}

void push_down( int id )
{
    if ( tree[id].color )
    {//lazy
        tree[rid].color = tree[id].color;
        tree[lid].color = tree[id].color;
        tree[id].color = 0;
    }
}

void update( int id ,int l,int r,int val )
{
    if ( tree[id].l==l&&tree[id].r==r )
    {
        tree[id].color = val;
        return;
    }
    push_down(id);
    int mid = ( tree[id].l+tree[id].r )/2;
    if ( r <= mid )
        update(lid,l,r,val);
    else if ( l > mid )
        update(rid,l,r,val);
    else
    {
        update(lid,l,mid,val);
        update(rid,mid+1,r,val);
    }
}

void query( int id, int l,int r )
{
    if ( tree[id].l<=l&&tree[id].r>=r )
    {
        if ( tree[id].color )
        {
            num[tot++] = tree[id].color;
            return;
        }
    }
    int mid = ( tree[id].l+tree[id].r )/2;
    if ( r <= mid )
        query(lid,l,r);
    else if ( l > mid )
        query(rid,l,r);
    else
    {
        query(lid,l,mid);
        query(rid,mid+1,r);
    }
}


int main(void)
{
    int n,m;
    while ( scanf("%d%d",&n,&m)!=EOF )
    {
        if ( n==0&&m==0 )
            break;
        build(1,1,n);
        string str;
        while ( m-- )
        {
            cin>>str;
            if ( str[0]=='P' )
            {
                int t1,t2,t3; scanf("%d%d%d",&t1,&t2,&t3);
                update(1,t1,t2,t3);
            }
            else if ( str[0]=='Q' )
            {
                int t1,t2; scanf("%d%d",&t1,&t2);
                query(1,t1,t2);
                sort(num,num+tot);
                printf("%d",num[0]);
                for ( int i = 1;i < tot;i++ )
                {
                    if ( num[i]!=num[i-1] )
                    {
                        printf(" %d",num[i]);
                    }
                }
                puts("");
                memset(num,0,sizeof(num));
                tot = 0;
            }
        }
        memset(num,0,sizeof(num));
        tot = 0;
    }

    return 0;
}