let arr1 = [1, 2, 3, 4, 5] let arr2 = [1, 2, 3, 4 ,5] // first to the last arr1.push(arr1.shift()) // [2, 3, 4, 5, 1] // last to the first arr2.unshift(arr2.pop()) // [5, 1, 2, 3, 4]