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codingbat.py

#!/usr/bin/env python

__author__ = 'Rio'


def sleep_in(weekday, vacation):
    return True if not weekday or vacation else False


def monkey_trouble(a_smile, b_smile):
    return a_smile == b_smile


def sum_double(a, b):
    return a + b if a != b else (a + b) * 2


def diff21(n):
    return abs(n - 21) if n < 21 else 2 * abs(n - 21)


def count_evens(nums):
    return len([val for val in nums if val % 2 == 0])


def big_diff(nums):
    return max(nums) - min(nums)


def centered_average(nums):
    n, mid = len(nums), len(nums) // 2
    nums.sort()
    if n % 2 != 0:
        return nums[mid]
    else:
        return (nums[mid - 1] + nums[mid]) // 2


def near_hundred(n):
    return True if abs(n - 100) <= 10 or abs(n - 200) <= 10 else False


def pos_neg(a, b, negative):
    return a < 0 and b < 0 if negative else a * b < 0

def not_string(str):
    return str if str.startswith('not') else 'not ' + str


def makes10(a, b):
    return True if a == 10 or b == 10 or a + b == 10 else False


def missing_char(str, n):
    return str[:n] + str[n + 1:]


def front_back(str):
    return str[-1] + str[1:-1] + str[0] if len(str) > 1 else str


def front3(str):
    return str[:3] * 3 if len(str) >= 3 else str * 3


def string_times(str, n):
    return str * n


def front_times(str, n):
    return str[:3] * n if len(str) >= 3 else str * n


def string_bits(str):
    return ''.join([str[i] for i in range(len(str)) if i % 2 == 0])


def string_splosion(str):
    return ''.join([str[:i] for i in range(len(str)+1)])


def last2(str):
    if len(str) < 2: return 0

    count, last = 0, str[-2:]
    for i in range(len(str) - 2):
        sub = str[i: i+2]
        if sub == last: count += 1

    return count


def string_match(a, b):
    count, length = 0, min(len(a), len(b))
    for i in xrange(length-1):
        if a[i] == b[i] and a[i+1] == b[i+1]: count += 1
    return count


def array_count9(nums):
    return len([val for val in nums if val == 9])


def array_front9(nums):
    return 9 in nums and nums.index(9) <= 3


def first_last6(nums):
    return nums[0] == 6 or nums[-1] == 6


def array123(nums):
    return '123' in ''.join(map(str, nums))


def hello_name(name):  
    return 'Hello ' + name + '!'


def make_abba(a, b): 
    return a + b * 2 + a


def make_tags(tag, word): 
    return '<{0}>{1}</{0}>'.format(tag, word)


def make_out_word(out, word): 
    return '{0}{1}{2}'.format(out[:2], word, out[2:])


def extra_end(str):
    if len(str) >= 2: return str[-2:] * 3
    

def first_two(str):
    return str[:2] if len(str) >= 2 else str
    

def first_half(str):
    return str[:len(str)//2]
    

def without_end(str):
    return str[1:-1] if len(str) > 2 else ''
    

def combo_string(a, b):
    return a+b+a if len(a) < len(b) else b+a+b
    



def non_start(a, b):
    if len(a) >= 1 and len(b) >= 1:
        return a[1:]+b[1:] 
        
        
def left2(str):
    return str[2:]+str[:2] if len(str) > 2 else str
    

def sum3(nums):
    return sum(nums)




def same_first_last(nums):
    return nums[0] == nums[-1] if len(nums) >= 1 else False


def common_end(a, b):
    return a[0] == b[0] or a[-1] == b[-1]