Given an integer, return its base 7 string representation.
Example 1:
Input: 100
Output: "202"
Example 2:
Input: -7
Output: "-10"
Note: The input will be in range of [-1e7, 1e7].
class Solution(object):
def convertToBase7(self, num):
abs_num = abs(num)
base_str = ''
while abs_num >= 7:
base_str += str(int(abs_num) % 7)
abs_num /= 7
base_str += str(int(abs_num))
if num >= 0:
return base_str[::-1]
else:
return '-' + base_str[::-1]