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 arrays. 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 validateStackSequences(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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