344 Reverse String

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"]
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func reverseString(s []byte]) {
	i , j := 0, len(s) - 1
	for i < j {
		temp := s[i]
		s[i] = s[j]
		i++
		s[j] = temp
		j--
	}
	fmt.Println(s)
}
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class Solution:
    def reverseString(self, s: List[str]) -> None:
        """
        Do not return anything, modify s in-place instead.
        """
        n = len(s)
        for i in range(n//2):
            s[i], s[n-i-1] = s[n-i-1], s[i]
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public void reverseString(char[] s) {
    int i = 0;
    int j = s.length - 1;
    while (i < j) {
        char temp = s[i];
        s[i++] = s[j];
        s[j--] = temp;
    }
    System.out.println(s);
}