Strange Container

[aklepatc]

Code a data structure with 2 operations: push() and popMostFrequent().

Most of the meat is in the comments/discussion below.

Comments

[aklepatc]

This memory is not completely lost for the lifetime of the process. It is freed/reclaimed every time the slice gets reallocated by append().

So it is only "leaked" until the next append() causes reallocation. "Normally" though, append() does not cause reallocation. So you don't know for sure when (if ever) the memory is returned to the process.

You keep truncating the buffer on the left... So you might be causing reallocation on every loop iteration? I'm not too sure TBH.

Language standard does not (precisely) specify reallocation policy. AFAIU in practice reallocation doubles capacity. But I am not too sure what the base number is: original capacity or original length. So I cannot confidently reason about how many reallocations your code would cause.