leetcode 344. Reverse String

Seawolf

1. Write a function that reverses a string. The input string is given as an array of characters char[].
   
2. 
   
3. Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.
   
4. 
   
5. You may assume all the characters consist of printable ascii characters.
   
6. 
   
7. 
   
8. 
   
9. Example 1:
   
10. 
    
11. Input: ["h","e","l","l","o"]
    
12. Output: ["o","l","l","e","h"]
    
13. Example 2:
    
14. 
    
15. Input: ["H","a","n","n","a","h"]
    
16. Output: ["h","a","n","n","a","H"]

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1. class Solution {
   
2.     public void reverseString(char[] s) {
   
3.         int i = 0;
   
4.         while(s.length -1 - i - i >=1 && i < s.length - 1){
   
5.             
   
6.             char temp = s[i];
   
7.             s[i] = s[s.length - 1 - i];
   
8.             s[s.length - 1-i] = temp;
   
9.             i++;
   
10.         }
    
11.     }
    
12. }

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