Tags: "leetcode", "hashmap", access_time 1-min read

Edit this post on Github

Find Anagram Mappings

Created: September 17, 2019 by [lek-tin]

Last updated: September 17, 2019

Given two lists A and B, and B is an anagram of A. B is an anagram of A means B is made by randomizing the order of the elements in A.

We want to find an index mapping P, from A to B. A mapping P[i] = j means the ith element in A appears in B at index j.

These lists A and B may contain duplicates. If there are multiple answers, output any of them.

For example, given

A = [12, 28, 46, 32, 50]
B = [50, 12, 32, 46, 28]

We should return

[1, 4, 3, 2, 0]
as P[0] = 1 because the 0th element of A appears at B[1], and P[1] = 4 because the 1st element of A appears at B[4], and so on.

Note

  1. A, B have equal lengths in range [1, 100].
  2. A[i], B[i] are integers in range [0, 10^5].

Solution

class Solution:
    def anagramMappings(self, A: List[int], B: List[int]) -> List[int]:
        n = len(A)

        dict_B = {}
        for i in range(n):
            num = B[i]
            dict_B[num] = i

        P = []
        for num in A:
            P.append(dict_B[num])

        return P