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Update Reverse Words in a String

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Original file line number	Diff line number	Diff line change
`@@ -73,3 +73,37 @@ public:`
`73`	`73`	`return ans ;`
`74`	`74`	`}`
`75`	`75`	`};`
	`76`	`+`
	`77`	`+`
	`78`	`+// 法三:先用 reverse 的技巧,並在 reverse 的過程中挑掉連續的空格,這樣就會得到一個單字內被 reverse,但順序正確的字串`
	`79`	`+接著再把每個單字 reverse 回來即可`
	`80`	`+`
	`81`	`+Time Complexity : O(n) for each character at most reverses two times`
	`82`	`+Space Complexity : O(n) for the output string (沒有使用額外空間)`
	`83`	`+`
	`84`	`+class Solution {`
	`85`	`+public:`
	`86`	`+ string reverseWords(string s) {`
	`87`	`+ string ans ;`
	`88`	`+ int first = 0 ;`
	`89`	`+ while ( s[first] == ' ' )`
	`90`	`+ first++ ;`
	`91`	`+`
	`92`	`+ for(int i = s.length() - 1 ; i >= first ; i--) {`
	`93`	`+ if ( s[i] == ' ' && (i == s.length() - 1 \|\| i == 0 \|\| s[i + 1] == ' ') )`
	`94`	`+ continue ;`
	`95`	`+ ans += s[i] ;`
	`96`	`+ }`
	`97`	`+`
	`98`	`+ int start = 0 ;`
	`99`	`+ for(int i = 0 ; i < ans.length() ; i++) {`
	`100`	`+ if ( ans[i] == ' ' ) {`
	`101`	`+ reverse( ans.begin() + start , ans.begin() + i ) ;`
	`102`	`+ start = i + 1 ;`
	`103`	`+ }`
	`104`	`+ }`
	`105`	`+ reverse( ans.begin() + start , ans.end() ) ;`
	`106`	`+`
	`107`	`+ return ans ;`
	`108`	`+ }`
	`109`	`+};`

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