246. Strobogrammatic Number

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

class Solution {
    // ask if 00 is a valid strobogrammatic number! Here is true!
    public boolean isStrobogrammatic(String num) {
        for(int i = 0, j = num.length() -1; i <= j; i++, j--){
            if(!"00 11 696 88".contains(num.charAt(i) + "" + num.charAt(j)))
                return false;
        }
        return true;
    }
}

class Solution(object):
    def isStrobogrammatic(self, num):
        """
        :type num: str
        :rtype: bool
        """
        s = set(['00', '11', '69', '96', '88'])
        i , j  = 0, len(num) - 1
        while(i <= j):
            if '{}{}'.format(num[i], num[j]) not in s:
                print('{}{}'.format(num[i], num[j]))
                return False
            i+=1
            j-=1
        return True