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 listOct 4, 2026 14:34Karthik ReddyKarthik ReddyError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 4, 2026 14:34076,418,97262,560,0003,344,0002,113,536expected "2515839 ", got "ops 1000000 oc dec: 1 413 451 479 503 526 548 572 600 639 825 | final levels 136 lo 2513 hi 2883 consumed 470406 2515839 "
2Oct 4, 2026 14:340122,027,784107,585,0003,263,0002,113,536expected "1001000 ", got "ops 1000000 oc dec: 1 414 450 477 500 522 544 567 595 632 838 | final levels 71 lo 1001 hi 1178 consumed 472618 1001000 "
3Oct 4, 2026 14:340116,560,875102,439,0003,091,0002,113,536expected "1469388 ", got "ops 1000000 oc dec: 1 418 455 481 504 526 548 572 601 639 817 | final levels 94 lo 1469 hi 1756 consumed 466413 1469388 "