LeetCode: 557Reverse Words in a String III(easy)
题目：
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.
代码：
1 class Solution { 2 public: 3 string reverseWords(string s) { 4 stack<char> tem; 5 string result; 6 string s1 = s + ' '; 7 for (auto c : s1){ 8 if ( c != ' ') 9 tem.push(c); 10 else { 11 while(!tem.empty()){ 12 result = result + tem.top(); 13 tem.pop(); 14 } 15 result = result + ' '; 16 } 17 } 18 result = result.substr(0, result.length()-1); 19 return result; 20 } 21 };
运行时间：772ms
别人的：
1 class Solution { 2 public: 3 4 string reverseWords(string s) { 5 string result(s.length(), 32); 6 int start = 0; 7 int end = s.find(32); 8 while (end != -1) { 9 for (int i = start; i < end; ++i) 10 result[end - (i - start) - 1] = s[i]; 11 start = end + 1; 12 end = s.find(32, start); 13 } 14 end = s.length(); 15 for (int i = start; i < end; ++i) 16 result[end - (i - start) - 1] = s[i]; 17 return result; 18 } 19 };
运行时间：26mm
栈比较耗时间？
