911e7f218e15 ·

基于Swift4，最后一题字符串处理的题目可以通过字符串索引的方式来做：
func reversedByWord(sentence: String) -> String {
var lastWordIndex = sentence.startIndex
var copySentence = sentence
var ans = ""
copySentence.append(" ")
for i in copySentence.indices {
if copySentence[i] == " " {
let subString = String(copySentence[lastWordIndex..<i].reversed())
lastWordIndex = copySentence.index(after: i)
ans += subString + " "
}
}
ans.removeLast()
return ans
}

reversedByWord(sentence: "The quick brown fox jumps over the lazy dog")

func reversedSantence(sentence: String) -> String {
let ans = String(reversedByWord(sentence: sentence).reversed())
return ans
}
reversedSantence(sentence: "the sky is blue")

Bryant_2423 评论自Swift 算法实战之路：数组，字符串，集合，与字典