[LeetCode] 344. Reverse String
grandyang opened this issue · comments
Write a function that reverses a string. The input string is given as an array of characters char[]
.
Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.
You may assume all the characters consist of printable ascii characters.
Example 1:
Input: ["h","e","l","l","o"]
Output: ["o","l","l","e","h"]
Example 2:
Input: ["H","a","n","n","a","h"]
Output: ["h","a","n","n","a","H"]
这道题没什么难度,直接从两头往中间走,同时交换两边的字符即可,参见代码如下:
解法一:
class Solution {
public:
void reverseString(vector<char>& s) {
int left = 0, right = (int)s.size() - 1;
while (left < right) {
char t = s[left];
s[left++] = s[right];
s[right--] = t;
}
}
};
我们也可以用 swap 函数来帮助我们翻转:
解法二:
class Solution {
public:
void reverseString(vector<char>& s) {
int left = 0, right = (int)s.size() - 1;
while (left < right) {
swap(s[left++], s[right--]);
}
}
};
Github 同步地址:
类似题目:
参考资料:
https://leetcode.com/problems/reverse-string/
https://leetcode.com/problems/reverse-string/discuss/80935/Simple-C%2B%2B-solution