Fixed-Capacity Ring Buffer Window Sum

You maintain a fixed-capacity buffer that always holds at most the k most recently appended values. When a new value arrives and the buffer is already full, the oldest value is evicted to make room.

The first line gives q and the capacity k. Then q commands follow:

• APPEND x — append the integer x. If the buffer already holds k values, first evict the oldest. Produces no output.
• SUM — print the sum of the values currently in the buffer (0 if it is empty).
• SIZE — print how many values are currently in the buffer (between 0 and k).

Because the buffer only ever holds the last k appended values, SUM is exactly the running total over that trailing window.

Input format

Line 1: two integers q and k. Each of the next q lines is APPEND x, SUM, or SIZE.

Output format

For each SUM command print the current window sum; for each SIZE command print the current element count. Print answers in command order, one per line.

Constraints

• 1 ≤ q ≤ 100000
• 1 ≤ k ≤ 100000
• -1000000 ≤ x ≤ 1000000
• Every command is exactly one of the three forms above.