heap

DSA: sorted order, subarray

Intuition
Heaps are incredibly useful for problems that have some kind of sorted property, and a subarray is usually the structure of interest.

Implementation

min_heap = []
smallest_seen_at_every_index = []
for num in nums:
	heappush(heap, num)
	smallest_seen_at_every_index.append(heap[0])
return smallest_seen_at_every_index

Visual