Counting Valleys - Hackerrank Solution

 Check out the counting valleys question here: Hackerrank question

The picturization of the problem:

Suppose the input is: UDDDUDUU

Then, 

Answer: Valley level is 1. Because hiker stepped this way only.

To solve this problem:

Initially, assumed U = 1, D = -1 & altitude=0

Then, iterated till total steps-1. Whenever altitude(height) that is sea level is 0 & the last step is 'U" I have incremented the valley by 1 (because valley level is considered only when hiker's last step is 'U" & at the sea level).

When all the elements are traversed it returned the final valley's value that's our final result.

Solution:

def countingValleys(steps, path):

    # Write your code here

    

    altitude = 0

    valley = 0

    dict = {

        "U": 1,

        "D": -1

    }

    for eachstep in range(steps):

        altitude += dict[path[eachstep]] # calculating hiker's each step

        if altitude == 0 and path[eachstep] == "U":

            valley += 1

    return valley