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# 01/15/2022 344

using two poniters. left is from the start of the array. right is from the end of the array. While (left < right) swap value and move left pointer to right one step and move the right pointer left step.

Time Space O(N)

Space O(1)

class Solution { public void reverseString(char\[] s) {

```
    //two pointers
    int left = 0, right = s.length - 1;
    
    while(left < right){
            char temp = s[left];
            s[left++] = s[right];
            s[right--] = temp;
        
    }
    
}
```

}