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344. Reverse String
Description
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 <= 105s[i]is a printable ascii character.
Solutions
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class Solution { public void reverseString(char[] s) { for (int i = 0, j = s.length - 1; i < j; ++i, --j) { char t = s[i]; s[i] = s[j]; s[j] = t; } } } -
class Solution { public: void reverseString(vector<char>& s) { for (int i = 0, j = s.size() - 1; i < j;) { swap(s[i++], s[j--]); } } }; -
class Solution: def reverseString(self, s: List[str]) -> None: """ Do not return anything, modify s in-place instead. """ s[:] = s[::-1] ############# class Solution: def reverseString(self, s: List[str]) -> None: i, j = 0, len(s) - 1 while i < j: s[i], s[j] = s[j], s[i] i, j = i + 1, j - 1 -
func reverseString(s []byte) { for i, j := 0, len(s)-1; i < j; i, j = i+1, j-1 { s[i], s[j] = s[j], s[i] } } -
/** Do not return anything, modify s in-place instead. */ function reverseString(s: string[]): void { for (let i = 0, j = s.length - 1; i < j; ++i, --j) { [s[i], s[j]] = [s[j], s[i]]; } } -
/** * @param {character[]} s * @return {void} Do not return anything, modify s in-place instead. */ var reverseString = function (s) { for (let i = 0, j = s.length - 1; i < j; ++i, --j) { [s[i], s[j]] = [s[j], s[i]]; } }; -
impl Solution { pub fn reverse_string(s: &mut Vec<char>) { let mut i = 0; let mut j = s.len() - 1; while i < j { s.swap(i, j); i += 1; j -= 1; } } }