Dsa
Stack
Warm-up
The Loading Dock
A warehouse uses a Last-In-First-Out (LIFO) stack for crates. You are given a series of logs: 'IN id' means a crate with a specific integer ID was loaded onto the stack, and 'OUT' means the top crate was removed. Your task is to output the ID of the crate that is removed during each 'OUT' operation. If 'OUT' is called on an empty stack, print 'EMPTY'.
Example:
Input: IN 101, IN 102, OUT, IN 103, OUT
Output: 102 103
Key concepts
stackvalidation
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