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Leetcode
Easy
Strings
Arrays
Reverse String
Reverse the characters of a string or character array in place.
Acceptance 0%
Problem Statement
Problem
Given a sequence of characters, reverse the order of the characters in place.
You should modify the input character array directly using only extra space.
Notes
- The input is typically provided as a mutable array of characters.
- The order of all characters must be reversed.
- No new array should be used for the main solution.
Input Format
- A mutable array of characters
s. - The array may be empty.
Output Format
- Modify
sin place so that its characters appear in reverse order.
Constraints
- Use extra space.
- A linear-time solution is expected.
Examples
Sample cases returned by the problem API.
Example 1
Input
s = ['h','e','l','l','o']
Output
['o','l','l','e','h']
Explanation
Swap the first and last characters, then continue inward until the pointers meet.
Example 2
Input
s = ['H','a','n','n','a','h']
Output
['h','a','n','n','a','H']
Explanation
Reversing the array places the last character first and the first character last.
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