344. Reverse String - June day 4
link to leedcode problem definition
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"]
This can be solved with an approach called two pointers:
- Iterate through the array of charecters till half
- Swap chars from start and end
class Solution {
public void reverseString(char[] s) {
var size = s.length;
for(int i = 0; i < size / 2; i++) {
char c = s[i];
s[i] = s[size - i - 1];
s[size - i - 1] = c;
}
}
}