DIY: Validate Stack Sequences
Solve the interview question "Validate Stack Sequences" in this lesson.
We'll cover the following
Problem statement
You are provided with two stack sequences, pushed
and popped
, with distinct values. Return true
if and only if this could have been the result of a sequence of push
and pop
operations on an initially empty stack.
Input
The input will be two lists. The following is an example input:
pushed = [1,2,3,4,5]
popped = [1,2,3,4,5]
Output
The output will be a Boolean representing whether these sequences of push and pop operations could have been interleaved and performed on a valid stack that was initially empty. The following is an example output:
true
The following operation would result in an empty stack:
push(1), pop(1), push(2), pop(2), push(3), pop(3), push(4), pop(4), push(5), pop(5)
Coding exercise
Implement the validate_stack_sequences(pushed, popped)
function, where pushed
and popped
are the two stack sequences. The function returns either true
or false
depending on whether the stack was initially empty or not.
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