leetCode 344. Reverse String 字符串

344. Reverse StringWrite a function that takes a string as input and returns the string reversed.Example:
Given s = "hello", return "olleh".
思路1：使用一个新的string来存放结果。

class Solution {
public:
string reverseString(string s) {
int len = s.size();
string result;
for(int n = 0; n < len; n++)
{
result.append(1,s.at(len - 1 - n));
}
return result;
}
};

思路2：修改原来string直接得到结果。

class Solution {
public:
string reverseString(string s) {
int len = s.size();
for (int i = 0; i < len / 2 ; i++)
{
char a = s[i];
s[i] = s[len - 1 - i];
s[len - 1 - i] = a;
}
return s;
}
};

2016-08-10 13:04:05