function exam04(array){ //declare variables let countSwap = 0; let n = array.length; for (let i = 1; i < n; i++) { // extract the elements let current = array[i]; let j = i-1; while ((j > -1) && (current < array[j])) { array[j+1] = array[j]; j--; countSwap++; // count swap } array[j+1] = current; } return countSwap; } function test_01() { if (exam04([2, 1, 3, 1, 2]) === 4) { console.log("pass"); } else { console.log("fail"); } } test_01();