LeetCode之Shortest Distance to a Character（Kotlin）

問題： Given a string S and a character C, return an array of integers representing the shortest distance from the character C in the string.

Example 1:

Input: S = "loveleetcode", C = 'e'
Output: [3, 2, 1, 0, 1, 0, 0, 1, 2, 2, 1, 0]

Note:

S string length is in [1, 10000].
C is a single character, and guaranteed to be in string S.
All letters in S and C are lowercase.
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方法： 先正向遍歷，遍歷出S中所有字元正向距離C的距離，然後反向遍歷，遍歷出S中所有字元反向距離C的距離，最後取正向距離和反向距離的最小值的集合即為最終結果。

具體實現：

class ShortestDistanceToACharacter {
    fun shortestToChar(S: String, C: Char): IntArray {
        val result = mutableListOf<Int>()
        var pre = Int.MIN_VALUE / 2
        for (index in S.indices) {
            if (S[index] == C) {
                pre = index
            }
            result.add(index - pre)
        }
        pre = Int.MAX_VALUE / 2
        for (index in S.lastIndex downTo 0) {
            if (S[index] == C) {
                pre = index
            }
            result[index] = Math.min(result[index], pre - index)
        }
        return result.toIntArray()
    }
}

fun main(args: Array<String>) {
    val shortestDistanceToACharacter = ShortestDistanceToACharacter()
    val S = "loveleetcode"
    val C = 'e'
    CommonUtils.printArray(shortestDistanceToACharacter.shortestToChar(S, C).toTypedArray())
}
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有問題隨時溝通

具體程式碼實現可以參考Github