Temp solutions to theReq problems solving in Python

rand7.py

# If you have access to a function that returns a random integer from one to five,
# write another function which returns a random integer from one to seven.

import random


class Solution():

    def rand5(self):
        return random.randint(1, 5)

    def rand7(self):
        while True:
            r = 5 * (self.rand5() - 1) + self.rand5()
            if r <= 21:
                break
        return r % 7 + 1

s = Solution()
print s.rand7()

reverse_string.py

# Write an iterative function to reverse a string. 
# Do the same thing as a recursive function.


class Solution(object):

    def s_reverse(self, s):
        length = len(s)
        tmp = []
        for i in range(length - 1, -1, -1):
            tmp.append(s[i])
        return "".join(tmp)

    def r_reverse(self, s):
        if len(s) == 0:
            return ""
        else:
            return s[-1] + self.r_reverse(s[:-1])

s = Solution()
print s.s_reverse("Hello!")
print s.r_reverse("Hello!")