function avoidObstacles(nums) {
    let jumpNumber = 2;//start at 2 because 0 and 1 won't work
    //add zero as starting point in array
    nums.push(0);
    let obstacles = nums.sort();
    
   while(obstacles.every(
            function(obstacle, index, array){
                //check that adding step to each value doesn't equal the next
                return jumpNumber+obstacle !== array[index+1];
            })===false){
                jumpNumber++;               
            };
    return jumpNumber;
}



/**
* 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);
    });
});