Lakes_task2.py

# -*- coding: utf-8 -*-
"""
Created on Fri Sep 30 12:48:00 2016

@author: Vladislav.Zaimov
"""
lake_depth = 0
lake_water = 0

input_string = input("Input: ").lower()
for ch in input_string:
    if ch == 'h':
        if lake_depth > 0 :
            lake_water += lake_depth
        pass
    elif ch == 'd':
        if lake_depth >= 0 :
            lake_water += lake_depth + 0.5
        lake_depth += 1
        pass
    elif ch == 'u':
        if lake_depth > 0 :
            lake_water += lake_depth - 0.5
        lake_depth -= 1
    else:
        print("Ingnoring invalid value: {}".format(ch))
print(lake_water*1000)