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”]
- code
class Solution:
def reverseString(self, s: List[str]) -> None:
for i in range(len(s) // 2):
s[i], s[~i] = s[~i], s[i]
- code
class Solution:
def reverseString(self, s: List[str]) -> None:
l, r = 0, len(s)-1
while l < r:
s[l], s[r] = s[r], s[l]
l += 1
r -= 1