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poj 2777 Count Color(线段树)

Count Color
Time Limit: 1000MS Memory Limit: 65536K
Total Submissions: 35248 Accepted: 10622

Description

Chosen Problem Solving and Program design as an optional course, you are required to solve all kinds of problems. Here, we get a new problem. 

There is a very long board with length L centimeter, L is a positive integer, so we can evenly divide the board into L segments, and they are labeled by 1, 2, ... L from left to right, each is 1 centimeter long. Now we have to color the board - one segment with only one color. We can do following two operations on the board: 

1. "C A B C" Color the board from segment A to segment B with color C. 
2. "P A B" Output the number of different colors painted between segment A and segment B (including). 

In our daily life, we have very few words to describe a color (red, green, blue, yellow…), so you may assume that the total number of different colors T is very small. To make it simple, we express the names of colors as color 1, color 2, ... color T. At the beginning, the board was painted in color 1. Now the rest of problem is left to your. 

Input

First line of input contains L (1 <= L <= 100000), T (1 <= T <= 30) and O (1 <= O <= 100000). Here O denotes the number of operations. Following O lines, each contains "C A B C" or "P A B" (here A, B, C are integers, and A may be larger than B) as an operation defined previously.

Output

Ouput results of the output operation in order, each line contains a number.

Sample Input

2 2 4
C 1 1 2
P 1 2
C 2 2 2
P 1 2

Sample Output

2
1

题解及代码:


#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <set>
#include <map>
#include <queue>
#include <string>
#define maxn 100100
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define ALL %I64d
using namespace std;
typedef __int64  ll;
ll P_2[34];   //我们使用2^p代表第p中颜色
void init()
{
    P_2[0]=1;
    for(int i=1; i<=33; i++)
    {
        P_2[i]=2*P_2[i-1];
    }
}

struct segment
{
    int l,r;
    ll value;
    ll nv;
} son[maxn<<2];

void PushUp(int rt)
{                      //使用或操作,代表两端区间中颜色数合并
    son[rt].value=http://www.mamicode.com/son[rt<<1].value|son[rt<<1|1].value;>