Combination Sum - Recursive Backtracking - Leetcode 39

Combination Sum - Recursive Backtracking - Leetcode 39

#coding #leetcode #programming #interview

[Gamerayoub.]

is the time complexity for this O(2^n) ?

[kevinshenshiqi]

or just use a bottom-up dp solution with a time complexity of O(n*target) where n is the length of the list and target is the sum

[binbash]

You can do it in O(n) time complexity. Storing the values in set and check for target - nums[i] in set

[Mukesh-bfxt]

use two pointer pattern to solve this ...
for O(n)

[tonyc]

Why don’t these videos ever give a real example of how this is used

[tazanteflight]

These examples are so contrived. Do you pick a solution first, and then come up with some problem?

[SujanRai-fk]

Prefix sum or hashmap is best for this

[LocalhostTube]

Все это конечно круто и прикольно, вот только скажите, хоть кто-то где-то в реальной жизни это использует ?

[彩色糖果-ii]

Just asking u guys. If you are under interview coding round would u know to use this algorithm?

[jumpjump-ozpr]

This is boring, it is cooler if they only ask the number of possible combinations