Strobogrammatic Number
Created: October 2, 2019 by [lek-tin]
Last updated: October 2, 2019
A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down).
Write a function to determine if a number is strobogrammatic. The number is represented as a string.
Example 1
Input: "69"
Output: true
Example 2
Input: "88"
Output: true
Example 3
Input: "962"
Output: false
Solution
class Solution:
def isStrobogrammatic(self, num: str) -> bool:
pairs = {
1: 1,
6: 9,
8: 8,
9: 6,
0: 0
}
mid = len(num)//2+1
for i in range(mid):
leftNum = int(num[i])
rightNum = int(num[-i-1])
if leftNum not in pairs or pairs[leftNum] != rightNum:
return False
return True