better organization.

Author: RobisonTorres

Diff for: Challenges/BasicChallenges_7kyu/README.md

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+This repository contains my personal solution to the
+7_kyu's most popular challenges of the site codewars.

Diff for: Challenges/BasicChallenges_7kyu/add_binary.py

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+print('From Code Wars')
+print()
+
+def add_binary(a, b):
+
+    # This function sums two numbers (a, b),\
+    # and return the result in binary as str.
+    return f'{bin(a + b)[2:]}'
+    # Bin converts decimal to binary.
+    # return format(a + b, 'b') - clever.
+
+print(add_binary(1, 1))  # Outputs - 10
+print(add_binary(5, 9))  # Outputs - 1110

Diff for: Challenges/BasicChallenges_7kyu/arithmetic.py

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+print('From Code Wars')
+print()
+
+def arithmetic(a, b, operator):
+
+    # A simple calculator.
+    if operator == 'add':
+        return a + b
+    elif operator == 'subtract':
+        return a - b
+    elif operator == 'multiply':
+        return a * b
+    elif operator == 'divide':
+        return a / b
+
+print(arithmetic(5, 2, 'add'))  # Outputs - 7
+print(arithmetic(5, 2, 'subtract'))  # Outputs - 3

Diff for: Challenges/BasicChallenges_7kyu/calculate_years.py

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+print('From Code Wars')
+print()
+
+def calculate_years(principal, interest, tax, desired):
+
+    # This function calculates how many years\
+    # is necessary to reach a desired amount of money.
+    year = 0
+    while principal < desired:
+        principal += principal * interest - principal * interest * tax
+        year += 1
+    return year
+
+print(calculate_years(1000, 0.05, 0.18, 1100))
+# Outputs - 3 years. It means,\ starting with a principal\
+# of 1000 it will take 3 years to reach a desired amount of 1100.

Diff for: Challenges/BasicChallenges_7kyu/capitalize.py

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+print('From Code Wars')
+print()
+
+def capitalize(s):
+
+    # Given a string, capitalize the letters that occupy even indexes\
+    # and odd indexes separately. Ex: ['AbCdEf', 'aBcDeF']
+    a = ''.join([l.upper() if n % 2 else l for n, l in enumerate(s)])
+    return [a, a.swapcase()]
+
+print(capitalize('abracadabra'))  # Outputs - ['AbRaCaDaBrA', 'aBrAcAdAbRa']

Diff for: Challenges/BasicChallenges_7kyu/capitals.py

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+print('From Code Wars.')
+print()
+
+def capitals(word):
+
+    # This function takes a word and return all\
+    # indexes of capitalized letters.
+    return [a[0] for a in enumerate(word) if a[1].isupper()]
+
+print(capitals('CodEWaRs'))  # Outputs - [0, 3, 4, 6]

Diff for: Challenges/BasicChallenges_7kyu/check_coupon.py

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+from datetime import datetime
+print('From Code Wars.')
+print()
+
+def check_coupon(entered_code, correct_code, current_date, expiration_date):
+
+    # This function checks if a coupon is valid or not.
+    return entered_code is correct_code \
+           and datetime.strptime(current_date, "%B %d, %Y") \
+           <= datetime.strptime(expiration_date, "%B %d, %Y")
+
+print(check_coupon('123', '123', 'September 5, 2014', 'October 1, 2014'))
+# Outputs - True
+print(check_coupon('123a', '123', 'September 5, 2014', 'October 1, 2014'))
+# Outputs - False

Diff for: Challenges/BasicChallenges_7kyu/check_exam.py

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+print('From Code Wars.')
+print()
+
+def check_exam(arr1, arr2):
+
+    # This function checks an exam (arr1) with the student's answers (arr2),
+    # and return the total points or 0 if the total is negative.
+    return max(0, sum([0 if y == '' else 4 if x == y \
+        else - 1 for x, y in zip(arr1, arr2)]))
+
+print(check_exam(['a', 'a', 'c', 'b'], ['a', 'a', 'b',  '']))  # Outputs - 7

Diff for: Challenges/BasicChallenges_7kyu/count_sheep.py

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+print('If you can\'t sleep, just count sheep!!')
+print()
+
+def count_sheep(n):
+
+    # This function will count the amount of sheep based in any given number.
+    return ''.join([str(number) + ' sheep...' for number in range(1, n+1)])
+
+print(count_sheep(3))  # Outputs - 1 sheep...2 sheep...3 sheep...

Diff for: Challenges/BasicChallenges_7kyu/declare_winner.py

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+print('From Code Wars')
+print()
+
+class Fighter(object):
+    def __init__(self, name, health, damage_per_attack):
+        self.name = name
+        self.health = health
+        self.damage_per_attack = damage_per_attack
+
+    def __str__(self): return "Fighter({}, {}, {})"\
+        .format(self.name, self.health, self.damage_per_attack)
+    __repr__ = __str__
+
+def declare_winner(fighter1, fighter2, first_attacker):
+    cur, opp = (fighter1, fighter2) if first_attacker == fighter1.name \
+        else (fighter2, fighter1)
+    while cur.health > 0:
+        opp.health -= cur.damage_per_attack
+        cur, opp = opp, cur
+    return opp.name
+
+print(declare_winner(Fighter("Lew", 10, 2), Fighter("Harry", 5, 4), "Lew"))

Diff for: Challenges/BasicChallenges_7kyu/diff_array.py

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+print('From Code Wars')
+print()
+
+def number(bus_stops):
+
+    # This function calculates the difference between two numbers inside a list,
+    # nested in another list and return the total.
+    return sum([num[0] - num[1] for num in bus_stops])
+
+print(number([[10, 0], [3, 5], [5, 8]]))  # Outputs - 5

Diff for: Challenges/BasicChallenges_7kyu/divisors.py

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+print('From Code Wars')
+print()
+
+def divisors(integer):
+
+    # This function returns the divisors of any given number,
+    # or the number itself if it's prime number.
+    a = [num for num in range(2, integer) if integer % num == 0]
+    return a if len(a) != 0 else f'{integer} is prime.'
+    # An empty list equals to false.
+
+print(divisors(12))  # Outputs - [2, 3, 4, 6]
+print(divisors(13))  # Outputs - 13 is prime.

Diff for: Challenges/BasicChallenges_7kyu/divisorsa.py

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+print('From Code Wars')
+print()
+
+def divisors(n):
+
+    # This function counts the number of divisors of an integer.
+    return len([num for num in range(1, n + 1) if n % num == 0])
+    # return sum(1 for i in xrange(1, n + 1) if n % i == 0) - Other way.
+
+print(divisors(4))  # Outputs - [1, 2, 4] - 3
+print(divisors(30))  # Outputs - [1, 2, 3, 5, 6, 10, 15, 30] - 8

Diff for: Challenges/BasicChallenges_7kyu/dna_dict.py

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+print('From Code Wars')
+print()
+
+def dna_strand(dna):
+
+    # This function replaces letters of dna.
+    dna_pair = \
+        {
+            'A': 'T',
+            'T': 'A',
+            'C': 'G',
+            'G': 'C'
+        }
+    return ''.join([dna_pair[let] for let in dna])
+
+print(dna_strand('AGAT'))  # Outputs - TCTA

Diff for: Challenges/BasicChallenges_7kyu/dont_five.py

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+print('From Code Wars')
+print()
+
+def dont_give_me_five(start, end):
+
+    # This function counts how many numbers are in a range without '5' in it.
+    return len([num for num in range(start, end + 1) if '5' not in str(num)])
+
+print(dont_give_me_five(4, 17))  # Output - 12

Diff for: Challenges/BasicChallenges_7kyu/endswith.py

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+print('From Code Wars')
+print()
+
+def solution(string, ending):
+
+    # This function checks if the first argument ends with the second.
+    return string.endswith(ending)
+    # The endswith() method returns True if the string ends\
+    # with the specified value, otherwise False.
+
+print(solution('abcde', 'cde'))  # Outputs - True
+print(solution('abcde', 'abc'))  # Outputs - False

Diff for: Challenges/BasicChallenges_7kyu/evaporator.py

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+print('From Code Wars')
+print()
+
+def evaporator(content, evap_per_day, threshold):
+
+    # This program tests the life of an evaporator containing a gas. 
+    days = 0
+    limit = content * threshold/ 100
+    while content > limit:
+        content = content - (content * evap_per_day/ 100)
+        days += 1
+    return days
+
+print(evaporator(10, 10, 5))  # Outputs - 29 Days.

Diff for: Challenges/BasicChallenges_7kyu/factorial.py

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+print('From Code Wars')
+print()
+
+def factorial(n):
+
+    # This function will calculate the factorial of any given
+    # number between 1 and 12, and trow an error if the number
+    # is not between this interval.
+    fac = 1
+    if n < 0 or n > 12:
+        raise ValueError
+    else:
+        for num in range(1, n + 1):
+            fac *= num
+        return fac
+
+print(factorial(12))  # Outputs - 479001600
+print(factorial(13))  # Outputs - ValueError

Diff for: Challenges/BasicChallenges_7kyu/filter_letter.py

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+print('From Code Wars')
+print()
+
+def printer_error(s):
+
+    # This function counts letters above letter 'n' in a string,\
+    # and show the result beside the total amount of letters.
+    return str(len([let for let in s if let > 'm'])) + '/' + str(len(s))
+    # return '{}/{}'.format(len([let for let in s if let > 'm']), len(s))
+
+print(printer_error('aaaxbbbbyyhwawiwjjjwwm'))  # Outputs - 8/22

Diff for: Challenges/BasicChallenges_7kyu/filter_list.py

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+print('From Code Wars')
+print()
+
+def filter_list(l):
+
+    # This function removes strings from a list with strings and integers.
+    return [num for num in l if type(num) != str]
+
+print(filter_list([1, 2, 3, 'a', 'kajdçlkjfa']))  # Outputs - [1, 2, 3]

Diff for: Challenges/BasicChallenges_7kyu/filter_lista.py

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+print('From Code Wars')
+print()
+
+def friend(x):
+
+    # This function maintains only names with 4 letters.
+    return [name for name in x if name.isalpha() and len(name) == 4]
+
+names = ["Ryan", "Kieran", "Jason", "Yous", '123']
+print(friend(names))  # Outputs - ['Ryan', 'Yous']

Diff for: Challenges/BasicChallenges_7kyu/find.py

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+print('From Code Wars')
+print()
+
+def find(n):
+
+    # This function will return the sum of all multiples of 3 and 5,\
+    # of any given number.
+    return [num for num in range(1, n + 1) if num % 3 == 0 or num % 5 == 0]
+
+print(find(5))  # Outputs - 8 [3, 5]
+print(find(10))  # Outputs - 33 [3, 5, 6, 9, 10]

Diff for: Challenges/BasicChallenges_7kyu/find_short.py

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+print('From Code Wars')
+print()
+
+def find_short(s):
+
+    # This function returns the shortest word's length from a group of words.
+    return len(min(s.split(), key=len))
+
+print(find_short('Lets all go on holiday somewhere very cold'))  # Outputs - 2

Diff for: Challenges/BasicChallenges_7kyu/find_square.py

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+from math import sqrt, isqrt
+print('From Code Wars')
+
+def find_next_square(sq):
+
+    # Given an integer 'sq', it returns -1 for no square numbers,\
+    # and the next square number otherwise.
+    return -1 if sqrt(sq) != isqrt(sq) else (sqrt(sq) + 1) ** 2
+
+print(find_next_square(25))  # Outputs - 36
+print(find_next_square(26))  # Outputs - -1

Diff for: Challenges/BasicChallenges_7kyu/flatten_and_sort.py

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+print('From Code Wars')
+print()
+
+def flatten_and_sort(array):
+
+    # This function takes a 2D array, and return a  flatten
+    # version with all elements in ascending order.
+    return sorted([j for sub in array for j in sub])
+    # return sorted(sum(array, [])) - Clever.
+
+print(flatten_and_sort([[1, 3, 5], [100], [2, 4, 6]]))
+# Outputs - [1, 2, 3, 4, 5, 6, 100]

Diff for: Challenges/BasicChallenges_7kyu/fut_pop.py

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+print('From Code Wars')
+print()
+
+def nb_year(p0, percent, aug, p):
+
+    # This function calculates how many years\
+    # it necessary to reach a future population.
+    year = 0
+    while p0 < p:
+        p0 += int(p0 * (percent/100) + aug)
+        year += 1
+    return year
+
+print(nb_year(1000, 2, 50, 1200))
+# Outputs - 3 years. It means,\ starting with a population\
+# of 1000 it will take 3 years to reach a population of 1200.

Diff for: Challenges/BasicChallenges_7kyu/get_middle.py

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+print('From Code Wars')
+print()
+
+def get_middle(s):
+
+    # This function returns two middle characters of a string
+    # if the length is even, and only one middle character if
+    # the string length is odd.
+    a = int(len(s) / 2)
+    return s[a - 1] + s[a] if len(s) % 2 == 0 else s[a]
+
+print(get_middle('Toll'))  # Outputs - ol

Diff for: Challenges/BasicChallenges_7kyu/in_asc.py

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+print('From Code Wars')
+print()
+
+def in_asc_order(arr):
+
+    # This function determines whether a list is or not in ascending order.
+    return arr == sorted(arr)
+
+print(in_asc_order([1, 2, 4, 7, 19]))  # Outputs - True
+print(in_asc_order([1, 6, 10, 18, 2, 4, 20]))  # Outputs - False

Diff for: Challenges/BasicChallenges_7kyu/is_anagram.py

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+print('From Code Wars')
+print()
+
+def is_anagram(test, original):
+
+    # This function determines whether two words are anagram.
+    # Anagram definition : a word, phrase, or name formed by rearranging\
+    # the letters of another,\ such as cinema, formed from iceman.
+    return sorted(test.lower()) == sorted(original.lower())
+
+print(is_anagram('Buckethead', 'DeathCubeK'))  # Outputs - True.
+print(is_anagram('dumble', 'bumble'))  # Outputs - False.

Diff for: Challenges/BasicChallenges_7kyu/is_isogram.py

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+print('From Code Wars')
+print()
+
+def is_isogram(string):
+
+    # This function determines if a string is or not a isogram.
+    return True if len(set(string.lower())) == len(list(string.lower()))\
+        else False
+
+print(is_isogram('moOse'))  # Outputs - False
+print(is_isogram('isogram'))  # Outputs - True
+'''
+An isogram is a word that has no repeating letters, consecutive
+or non-consecutive. Implement a function that determines whether 
+a string that contains only letters is an isogram. Assume the empty 
+string is an isogram. Ignore letter case.
+'''