LeetCode之Find Anagram Mappings（Kotlin）

問題： Given two lists Aand 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.

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方法： 外層遍歷A中元素，內層遍歷B中元素，當A[i]與B[j]相等時輸出j並退出內層循環，A所有遍歷後全部輸出即爲結果，時間複雜度爲O(n*n)，空間複雜度爲O(1)。另一種方法是將B中元素添加到map結構中，遍歷A中元素經過map獲取在B中的index，時間複雜度爲O(n)，空間複雜度爲O(n)。

具體實現：

class FindAnagramMappings {
    fun anagramMappings(A: IntArray, B: IntArray): IntArray {
        val result = arrayListOf<Int>()
        for (i in A.indices) {
            for (j in B.indices) {
                if (A[i] == B[j]) {
                    result.add(j)
                    break
                }
            }
        }
        return result.toIntArray()
    }
}

fun main(args: Array<String>) {
    val A = intArrayOf(12, 28, 46, 32, 50)
    val B = intArrayOf(50, 12, 32, 46, 28)
    val findAnagramMappings = FindAnagramMappings()
    val result = findAnagramMappings.anagramMappings(A, B)
    for (e in result) {
        print("$e ,")
    }
}
複製代碼

有問題隨時溝通

具體代碼實現能夠參考Github