LeetCode之Find and Replace Pattern（Kotlin）

問題： You have a list of words and a pattern, and you want to know which words in words matches the pattern. A word matches the pattern if there exists a permutation of letters p so that after replacing every letter x in the pattern with p(x), we get the desired word. (Recall that a permutation of letters is a bijection from letters to letters: every letter maps to another letter, and no two letters map to the same letter.) Return a list of the words in words that match the given pattern. You may return the answer in any order.

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方法： 對於每一個字符串和映射字符串來講，若是映射關係中包含a->b，則map的key中包含a，則value中必包含b，反之，若是map的value中包含b，則key中必不包含a。根據如上規則，遍歷整個字符串組則能夠獲得符合映射關係的字符串，算法複雜度爲O(n)。

具體實現：

class FindAndReplacePattern {
    fun findAndReplacePattern(words: Array<String>, pattern: String): List<String> {
        val result = mutableListOf<String>()
        loop@ for (word in words) {
            val map = mutableMapOf<Char, Char>()
            for (i in word.indices) {
                if (map.containsKey(word[i])) {
                    val char = map[word[i]]
                    if (char != pattern[i]) {
                        continue@loop
                    }
                } else {
                    if (map.containsValue(pattern[i])) {
                        continue@loop
                    }
                }
                map.put(word[i], pattern[i])
            }
            result.add(word)
        }
        return result
    }
}

fun main(args: Array<String>) {
    val words = arrayOf("abc","deq","mee","aqq","dkd","ccc")
    val pattern = "abb"
    val findAndReplacePattern = FindAndReplacePattern()
    CommonUtils.printArray(findAndReplacePattern.findAndReplacePattern(words, pattern).toTypedArray())
}
複製代碼

有問題隨時溝通

具體代碼實現能夠參考Github