Order book Yuriy Lyfenko

Simulate a sell-side order book and calculate the cost of a final purchase as fast as possible.

Input

1,000,000 order updates on STDIN, one per line:

  • + <price> <size> – add a new sell order
  • - <position> – delete the order at the given position
  • = <size> – buy <size> shares from the top of the order book

After all updates are processed, buy 1,000 shares from the top of the order book.

Output

Print the total cost of the final 1,000-share purchase to STDOUT.

Order Book Rules

Orders are sorted by price ascending (lower is better). Orders at the same price are sorted by arrival time (earlier first). Position 0 is the best (lowest-price) offer.

The = (buy) operation consumes shares starting from position 0. If an order is fully consumed, it is removed from the book.

Example

Input Order book state
+ 1137 100 (1137,100)
+ 1130 10 (1130,10), (1137,100)
+ 1130 50 (1130,10), (1130,50), (1137,100)
- 0 (1130,50), (1137,100)
+ 1150 200 (1130,50), (1137,100), (1150,200)
= 200 (1150,150)

Total cost of the last buy: 50 * 1130 + 100 * 1137 + 50 * 1150.

Back to listApr 21, 2026 10:18Charles CabergsCharles CabergsScore: 55,181Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Apr 21, 2026 10:1953,51756,547,25830,039,0001,001,0002,453,504
2Apr 21, 2026 10:1953,72057,626,64829,148,0002,010,0002,379,776
3Apr 21, 2026 10:1954,64458,619,41130,672,0001,022,0002,408,448
4Apr 21, 2026 10:1954,96761,547,55429,889,0001,992,0002,453,504
5Apr 21, 2026 10:1955,18159,641,13430,005,0002,000,0002,506,752
6Apr 21, 2026 10:1955,69652,927,52029,276,0003,028,0002,482,176
7Apr 21, 2026 10:1955,72957,550,96129,293,0003,030,0002,256,896
8Apr 21, 2026 10:1957,22455,690,22331,179,0002,011,0002,301,952
9Apr 21, 2026 10:1957,62954,606,93832,413,0001,012,0002,428,928