## NOI '05 P2 - Maintaining a Sequence

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Points: 30 (partial)
Time limit: 0.6s
Memory limit: 64M

Problem type
##### National Olympiad in Informatics, China, 2005

Please write a program that maintains a sequence, supporting the following 6 operations:

Operation Input Format Description
1. Insert INSERT posi tot c1 c2 ... ctot After the -th number in the current sequence, insert a total of numbers: . Insertion to the beginning of the sequence will have equal to 0.
2. Delete DELETE posi tot Starting at the -th number in the current sequence, delete a total of consecutive numbers.
3. Modify MAKE-SAME posi tot c Starting at the -th number in the current sequence, change all the values of consecutive numbers to .
4. Reverse REVERSE posi tot Starting at the -th number in the current sequence, reverse the order of consecutive numbers.
5. Get Sum GET-SUM posi tot Starting at the -th number in the current sequence, output the sum of consecutive numbers. Note that is possible, in which case you should output .
6. Max Sum MAX-SUM Output the largest sum of any (non-empty) consecutive subsequence of the current sequence.

#### Input Specification

The first line of input contains two integers and , where is the initial length of the sequence and is the number of operations.

The second line of input contains integers, describing the initial sequence.

For the next lines, each line contains a command in one of the formats described above.

#### Output Specification

For each GET-SUM or MAX-SUM operation in the input, output the result of the query on a separate line.

#### Sample Input

9 8
2 -6 3 5 1 -5 -3 6 3
GET-SUM 5 4
MAX-SUM
INSERT 8 3 -5 7 2
DELETE 12 1
MAKE-SAME 3 3 2
REVERSE 3 6
GET-SUM 5 4
MAX-SUM

#### Sample Output

-1
10
1
10

#### Scoring

For each test case, your score will be determined as follows:

• If your program prints the correct answers to all GET-SUM operations at the correct locations in the output, then you will score of points.
• If your program prints the correct answers to all MAX-SUM operations at the correct locations in the output, then you will score of points.
• If your program correctly answers both types operations, then you will score of points.

Please note: If your program can only correctly process one type of operation, then ensure that operations of the other type each receive a corresponding line. Otherwise, we cannot guarantee that your score will be accurate.

#### Constraints

You may assume that at any given time, the sequence will contain at least 1 number.
The data in the input is guaranteed to be valid, and will always refer to existing positions in the sequence.

In test data worth at most of the points, the sequence may contain up to numbers at any given moment.
In test data worth of the points, the sequence may contain up to numbers at any given moment.

In test data worth of the points, the value of any number in the sequence will be in the range .
In test data worth of the points, , the sum of all inserted values will not exceed , and the input will not exceed 20MB.