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$ curl repovive.com/roadmaps/meta-interview-prep-v2/coding-patterns-i-arrays-strings-stacks/lc-791-custom-sort-string-implementation

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$ curl repovive.com/roadmaps/meta-interview-prep-v2/coding-patterns-i-arrays-strings-stacks/lc-791-custom-sort-string-implementation

Repovive

LeetCode 791 Custom Sort String - Implementation - Coding Patterns I: Arrays, Strings & Stacks | Meta Interview Prep | Repovive

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Meta Interview Prep6 sections · 147 units8h total

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LeetCode 791 Custom Sort String - Implementation

The code

Count character frequencies in s, then build the result by iterating through order first.

Here's the solution:

function customSortString(order, s):
    count = {}
    for ch in s:
        count[ch] = count.get(ch, 0) + 1
    result = []
    for ch in order:
        if ch in count:
            result.append(ch * count[ch])
            del count[ch]
    for ch in count:
        result.append(ch * count[ch])
    return "".join(result)

$O(|s|)$ time, $O(|s|)$ space.