leeCode344_Reverse string

1. Subject content

Write a function whose role is to reverse the input string. The input string is given in the form of a character array char[].

Don't allocate extra space to another array, you must modify the input array in place and use O(1) extra space to solve this problem.

You can assume that all characters in the array are printable characters in the ASCII code table.
Example 1 :
输入：["h","e","l","l","o"]
输出：["o","l","l","e","h"]

Example 2 :
输入：["H","a","n","n","a","h"]
输出：["h","a","n","n","a","H"]

2. Topic analysis

This is a fairly simple classic problem, directly on the problem solution: use double pointer to reverse the string.

Suppose the input string is ["h","e","l","l","0"]

• Define left and right to point to the first and last elements respectively
• When left <right, swap.
• The exchange is complete, left++, right–
• Until left == right

The specific process is shown in the figure below:

Three, code implementation

func reverseString(s []byte)  {
    
    
	left := 0
	right := len(s) - 1
	for left < right {
    
    
		s[left], s[right] = s[right], s[left]
		left++
		right--
	}
}