0246. Strobogrammatic Number

https://leetcode.com/problems/strobogrammatic-number

Description

Given a string num which represents an integer, return true if num is a strobogrammatic number.

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down).

Example 1:

**Input:** num = "69"
**Output:** true

Example 2:

**Input:** num = "88"
**Output:** true

Example 3:

**Input:** num = "962"
**Output:** false

Example 4:

**Input:** num = "1"
**Output:** true

Constraints:

• 1 <= num.length <= 50

• num consists of only digits.

• num does not contain any leading zeros except for zero itself.

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