344. Reverse String[Easy].md

• problem

  Write a function that reverses a string. The input string is given as an array of characters s.
  
  You must do this by modifying the input array in-place with O(1) extra memory.
  
   
  
  Example 1:
  
  Input: s = ["h","e","l","l","o"]
  Output: ["o","l","l","e","h"]
  Example 2:
  
  Input: s = ["H","a","n","n","a","h"]
  Output: ["h","a","n","n","a","H"]
   
  
  Constraints:
  
  1 <= s.length <= 105
  s[i] is a printable ascii character.
  Accepted
  1,387,156
  Submissions

• solve

  class Solution:
      def reverseString(self, s: List[str]) -> None:
          """
          Do not return anything, modify s in-place instead.
          """
          for c in range(len(s) // 2):
              tmp = s[c]
              s[c] = s[-1-c]
              s[-1-c] = tmp