#####   ######  #####    ###    #   #  ###  #   #  ######
##  ##  ##      ##  ##  ## ##   #   #   #   #   #  ##
#####   ####    #####   #   #   #   #   #   #   #  ####
##  #   ##      ##      ## ##    # #    #    # #   ##
##   #  ######  ##       ###      #    ###    #    ######

$ curl repovive.com/roadmaps/math-fundamentals/combinations/subsets-implementation-3

░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░████████████████████████████████████████████████████████████████████████████████████

#####   ######  #####    ###    #   #  ###  #   #  ######
##  ##  ##      ##  ##  ## ##   #   #   #   #   #  ##
#####   ####    #####   #   #   #   #   #   #   #  ####
##  #   ##      ##      ## ##    # #    #    # #   ##
##   #  ######  ##       ###      #    ###    #    ######

$ curl repovive.com/roadmaps/math-fundamentals/combinations/subsets-implementation-3

Repovive

Subsets - Implementation - Combinations | Math Fundamentals | Repovive

Repovive.

Math Fundamentals18 sections · 842 units13h total

Open in Course

Subsets - Implementation

The pseudocode

Here is the full solution:


function subsets(nums)
    result := []
    backtrack(nums, 0, [], result)
    return result

function backtrack(nums, start, current, result)
    add copy of current to result
    for i from start to length of nums - 1
        add nums[i] to current
        backtrack(nums, i + 1, current, result)
        remove last element from current

Time: $O(n \times 2^n)$ to generate and copy all $2^n$ subsets. Space: $O(n)$ for recursion depth.