Convert Integer to the Sum of Two No-Zero Integers

Problem

Qn - Convert Integer to the Sum of Two No-Zero Integers

Approach

Originally thought that we can randomly generate numbers and check if they are a zero integer, but then soon realised that we need a set to keep track of numbers that we have tried, that would make it $O(n)$ in both time and space. Then realised that we can do away with the set to keep track of the numbers and just do it iteratively, from 1 all the way to n.

Complexity

• Time: $O(n/2)$
• Space: $O(1)$

Code

class Solution:
    def getNoZeroIntegers(self, n: int) -> List[int]:
        def isZeroInteger(num):
            while num:
                if not num%10: return False
                num //= 10
            return True
 
        for i in range(1,n):
            if isZeroInteger(i) and isZeroInteger(n-i): return [i,n-i]