Descr iption

很多学校流行一种比较的习惯。老师们很喜欢询问，从某某到某某当中，分数最高的是多少。

这让很多学生很反感。



不管你喜不喜欢，现在需要你做的是，就是按照老师的要求，写一个程序，模拟老师的询问。当然，老师有时候需要更新某位同学的成绩。



Input

本题目包含多组测试，请处理到文件结束。

在每个测试的第一行，有两个正整数 N 和 M ( 0<N<=200000,0<M<5000 )，分别代表学生的数目和操作的数目。

学生ID编号分别从1编到N。

第二行包含N个整数，代表这N个学生的初始成绩，其中第i个数代表ID为i的学生的成绩。

接下来有M行。每一行有一个字符 C (只取 Q 或 U ) ，和两个正整数A，B。

当C为 Q 的时候，表示这是一条询问操作，它询问ID从A到B(包括A,B)的学生当中，成绩最高的是多少。

当C为 U 的时候，表示这是一条更新操作，要求把ID为A的学生的成绩更改为B。



Output

对于每一次询问操作，在一行里面输出最高成绩。



Sample Input

5 6

1 2 3 4 5

Q 1 5

U 3 6

Q 3 4

Q 4 5

U 2 9

Q 1 5



Sample Output

5

6

5

9

-Descr iption

Many schools have a relatively popular habit. Teachers are likely to ask, to certain of them from certain, with the highest score is.

This makes a lot of students are very offensive.



Whether you like it or not, you now need to do is, that in accordance with the requirements of the teacher to write a program to simulate the teacher asked. Of course, teachers sometimes need to update certain students achievements.

 

Input

This topic contains several test cases, handle to the end of the file.

In the first line of each test, there are two positive integers N and M (0 <N <= 200000,0 <M <5000), respectively represent the number of students and number of operations.

Student ID numbers were compiled from one to N.

The second line contains N integers, representing the N initial student achievement, the first of which is i i rep ID number of student achievement.

Then there are M lines. Each line has a character C (just take the　Q　or　U ), and two positi