reverse.js

let arr = [1, 2, 3, 4, 5];
let start = 0;
let end = arr.length - 1;

while (start < end) {
  let temp = arr[start];
  arr[start] = arr[end];
  arr[end] = temp;

  start++;
  end--;
}

console.log(arr); // Output: [5, 4, 3, 2, 1]