function avoidObstacles(nums) {
  let jump = nums.sort((a, b) => a - b)[0] + 1;
  let jumpSum = jump * 2;
  const setJumpSize = () => {
    if (nums.includes(jump) || nums.includes(jumpSum)) {
      jump += 1;
      jumpSum = jump * 2;
      setJumpSize();
    }
  };
  setJumpSize();

  const testJumpSize = () => {
    if (nums.includes(jumpSum)) setJumpSize();
    jumpSum += jump;
    if (nums.includes(jumpSum)) testJumpSize();
  };

  testJumpSize();
  return jump;
}



/**
* Test Suite 
*/
describe('avoidObstacles()', () => {
    it('returns minimal number of jumps in between numbers', () => {
        // arrange
        const nums = [5, 3, 6, 7, 9];
        
        // act
        const result = avoidObstacles(nums);

        // log
        console.log("result: ", result);
        
        // assert
        expect(result).toBe(4);
    });
});