Sort according to another array
Detailed guide and Python implementation for the 'Sort according to another array' problem.
Problem Statement
Write a function sort_by_order(arr1, arr2) that sorts the elements of arr1 according to the order defined by arr2. Elements in arr1 that appear in arr2 should come first in the order they appear in arr2. Elements not in arr2 should appear at the end in sorted (ascending) order.
- •1 <= len(arr1) <= 10^5
- •0 <= len(arr2) <= 100
- •Elements of arr2 are distinct
Examples
arr1 = [2, 1, 2, 5, 7, 1, 9, 3, 6, 8, 8], arr2 = [2, 1, 8, 3]
[2, 2, 1, 1, 8, 8, 3, 5, 6, 7, 9]
First all 2s, then 1s, then 8s, then 3s (order from arr2). Remaining [5,6,7,9] sorted ascending.
arr1 = [4, 5, 6], arr2 = [6, 4]
[6, 4, 5]
6 first, then 4 (per arr2 order). 5 is not in arr2, goes at end.
arr1 = [1, 2, 3], arr2 = []
[1, 2, 3]
No order specified, so sort ascending.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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