344. Reverse String #

Problem #

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"]

Problem Summary #

The problem asks us to reverse a string.

Solution Approach #

The solution idea for this problem is to use 2 pointers, with the two pointers moving toward each other, to continuously swap the first and last elements.

Code #

package leetcode

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