Reverse Words in a String III(C++)
阿新 • • 發佈:2018-12-15
繼續自己刷題之路。。。
Given a string, you need to reverse the order of characters in each word within a sentence while still preserving whitespace and initial word order.
Example 1:
Input: "Let's take LeetCode contest" Output: "s'teL ekat edoCteeL tsetnoc"
Note: In the string, each word is separated by single space and there will not be any extra space in the string.
題目的意思很清晰,就是將字串中的每個單詞反轉一下就可以了。
程式碼:
string reverseWords(string s) { int start = 0,end = 0,len = s.length(); while(start<len&&end<len){ while(end<len&&s[end]!=' ')end++; for(int i=start,j=end-1;i<j;i++,j--) swap(s[i],s[j]); start = ++end; } return s; }
解題方法還是有很多的,比如百度到的:
class Solution { public: string reverseWords(string s) { string res = "", t = ""; istringstream is(s); while (is >> t) { reverse(t.begin(), t.end()); res += t + " "; } s = res.substr(0,res.length()-1); return s; } };
使用字元流處理類stringstream來做的方法,相當簡單,就是按順序讀入每個單詞進行翻轉即可。
PS:補充一點別的,讀取字串空格的時候,C++中可以用getline(cin,字串名)的方法。(不學真的是忘了。。。)