diff --git a/problems/0151.翻转字符串里的单词.md b/problems/0151.翻转字符串里的单词.md index d03de421..0e25fc4d 100644 --- a/problems/0151.翻转字符串里的单词.md +++ b/problems/0151.翻转字符串里的单词.md @@ -758,7 +758,63 @@ func reverseWord(_ s: inout [Character]) { } ``` +Scala: +```scala +object Solution { + def reverseWords(s: String): String = { + var sb = removeSpace(s) // 移除多余的空格 + reverseString(sb, 0, sb.length - 1) // 翻转字符串 + reverseEachWord(sb) + sb.mkString + } + + // 移除多余的空格 + def removeSpace(s: String): Array[Char] = { + var start = 0 + var end = s.length - 1 + // 移除字符串前面的空格 + while (start < s.length && s(start) == ' ') start += 1 + // 移除字符串后面的空格 + while (end >= 0 && s(end) == ' ') end -= 1 + var sb = "" // String + // 当start小于等于end的时候,执行添加操作 + while (start <= end) { + var c = s(start) + // 当前字符不等于空,sb的最后一个字符不等于空的时候添加到sb + if (c != ' ' || sb(sb.length - 1) != ' ') { + sb ++= c.toString + } + start += 1 // 指针向右移动 + } + sb.toArray + } + + // 翻转字符串 + def reverseString(s: Array[Char], start: Int, end: Int): Unit = { + var (left, right) = (start, end) + while (left < right) { + var tmp = s(left) + s(left) = s(right) + s(right) = tmp + left += 1 + right -= 1 + } + } + + // 翻转每个单词 + def reverseEachWord(s: Array[Char]): Unit = { + var i = 0 + while (i < s.length) { + var j = i + 1 + // 向后迭代寻找每个单词的坐标 + while (j < s.length && s(j) != ' ') j += 1 + reverseString(s, i, j - 1) // 翻转每个单词 + i = j + 1 // i往后更新 + } + } +} +``` diff --git a/problems/剑指Offer58-II.左旋转字符串.md b/problems/剑指Offer58-II.左旋转字符串.md index fec83e1d..581ac1c7 100644 --- a/problems/剑指Offer58-II.左旋转字符串.md +++ b/problems/剑指Offer58-II.左旋转字符串.md @@ -290,7 +290,34 @@ func reverseString(_ s: inout [Character], startIndex: Int, endIndex: Int) { } ``` +Scala: +```scala +object Solution { + def reverseLeftWords(s: String, n: Int): String = { + var str = s.toCharArray // 转换为Array + // abcdefg => ba cdefg + reverseString(str, 0, n - 1) + // ba cdefg => ba gfedc + reverseString(str, n, str.length - 1) + // ba gfedc => cdefgab + reverseString(str, 0, str.length - 1) + // 最终返回,return关键字可以省略 + new String(str) + } + // 翻转字符串 + def reverseString(s: Array[Char], start: Int, end: Int): Unit = { + var (left, right) = (start, end) + while (left < right) { + var tmp = s(left) + s(left) = s(right) + s(right) = tmp + left += 1 + right -= 1 + } + } +} +```