Sort Array by Increasing Frequency - Leetcode 1636 - Python

0:00 - Read the problem
0:30 - Drawing Explanation
6:07 - Coding Explanation

leetcode 1636

#neetcode #leetcode #python

[axilie]

I use Java and it always amazes me how much shorter and less meandering Python is.

[deadlyecho]

You could also solve it using double counting sort, O(N), O(100) space and time complexity.

[SachinRajput]

I did it using a counter and a heap. I stored (count, -1 * n) in heap, so it kept both the orderings

[fiascogamingchannel]

initially sorting the array in desc order to deal with the desc order asked in ques for same freq is what i used

[sidazhong]

I use min heap + two hashmaps. and you write it in 3 lines?

hashmap = {}
for v in nums:
hashmap[v] = hashmap.get(v, 0) + 1

count = {}
for k, v in hashmap.items():
count.setdefault(v, []).append(k)

heap = []
for k, v in count.items():
heap.append((k, v))

heapq.heapify(heap)
rs = []
while heap:
curr = heapq.heappop(heap)
tmp = sorted((curr[1] * curr[0]), reverse = True)
rs = rs + tmp

return rs