Perform Operations on Array

You are given a series of operations to perform on an array. The operations include appending an integer, removing all occurrences of a specified integer, and querying the maximum subarray sum within a specified range. For the query operation, the maximum subarray sum is defined as the largest sum of any contiguous subarray within the given segment. Mathematically, if (a_1, a_2, \dots, a_n) represent the subarray, you must find (\max_{1 \leq i \leq j \leq n}\sum_{k=i}^j a_k).

The operations are provided in the following format:

1. Append(x): Append the integer (x) to the end of the array.
   
2. Remove(x): Remove all occurrences of the integer (x) from the array.
   
3. MaxSubArray(L, R): Compute the maximum subarray sum for the subarray from index (L) to (R) (both inclusive, with 1-indexing).
   
   It is recommended to use Kadane's algorithm to solve the maximum subarray problem efficiently. You may assume that every query operation refers to a non-empty subarray.

inputFormat

The input is read from standard input (stdin) and is structured as follows:

• The first line contains an integer \(Q\) denoting the number of operations.
• The next \(Q\) lines each contain an operation in one of the formats:
  • 1 x — Append the integer \(x\) to the array.
  • 2 x — Remove all occurrences of the integer \(x\) from the array.
  • 3 L R — Output the maximum subarray sum for the subarray from index \(L\) to \(R\) (1-indexed).

outputFormat

For each operation of type 3 (MaxSubArray query), output the resulting maximum subarray sum on a new line to standard output (stdout).## sample

7
1 1
1 -2
1 3
1 2
3 1 3
2 -2
3 1 3

3
6