const arrayPreviousLess = (nums) =>
  nums.map(
    (num, i, arr) =>
      arr
        .slice(0, i)
        .reverse()
        .find((el) => el < num) || -1
  );




/**
* Test Suite 
*/
describe('arrayPreviousLess()', () => {
  it("shift previous postions from the left to a smaller value or store -1", () => {
  // arrange
  const nums = [9, 5, 2, 8, 11, 1, 6];

  // act
  const result = arrayPreviousLess(nums);

  // log
  console.log("result: ", result);

  // assert
  expect(result).toEqual([-1, -1, -1, 2, 8, -1, 1]);
  });

  it("shift previous postions from the left to a smaller value or store -1", () => {
  // arrange
  const nums = [3, 5, 2, 4, 5, 3];

  // act
  const result = arrayPreviousLess(nums);

  // log
  console.log("result: ", result);

  // assert
  expect(result).toEqual([-1, 3, -1, 2, 4, 2]);
  });

});