<LeetCode OJ> 345. Reverse Vowels of a String

Total Accepted: 537 Total
Submissions: 1488 Difficulty: Easy

Write a function that takes a string as input and reverse only the vowels of a string.
Example 1:

Given s = "hello", return "holle".
Example 2:

Given s = "leetcode", return "leotcede".

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Two Pointers String

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(E) Reverse String

分析：

典型的双指针问题，注意边界条件即可！

class Solution {
public:
void swapchar(string &str,int pos1,int pos2)
{
char tmpch=str[pos2];
str[pos2]=str[pos1];
str[pos1]=tmpch;
}
string reverseVowels(string s) {
char base[10]={'a','e','i','o','u','A','E','I','O','U'};
set<char> seting(base,base+10);
int startpos=0,endpos=s.size()-1;
while(startpos < endpos )
{
while( startpos < endpos && seting.find(s[startpos]) == seting.end())//从左往右、新的、未被交换过的元音位置
startpos++;
while( startpos < endpos && seting.find(s[endpos]) == seting.end())
endpos--;
if(startpos < endpos)
swapchar(s,startpos++,endpos--);
}
return s;
}
};

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原文地址：http://blog.csdn.net/ebowtang/article/details/51228095

原作者博客：http://blog.csdn.net/ebowtang

本博客LeetCode题解索引：/article/3664871.html