Problem Description
Given a positive integer n, find two positive integers a and b such that both a and b do not contain the digit '0' in their decimal representation and a + b equals n. It is guaranteed that there is at least one such solution.
Key Insights
- A no-zero integer is defined as a positive integer that does not contain the digit '0'.
- We can iterate over potential values of a and calculate b = n - a.
- The main check for each candidate is ensuring that neither a nor b contains the digit '0'.
- Since n is up to 10⁴, iterating from 1 to n is efficient enough.
Space and Time Complexity
Time Complexity: O(n * log10(n)) in the worst case, because each number is converted to a string for checking zeros (the number of digits is proportional to log10(n)).
Space Complexity: O(1) apart from the space used for output.
Solution
We use an iterative approach by trying each possible value of a starting from 1 up to n-1. For each value of a, we compute b = n - a and then check if both a and b are no-zero integers by converting them to strings and checking for the presence of the character '0'. We stop as soon as we find such a pair and return it.
Key data structures: None required besides simple variables.
Algorithmic approach: Simple iteration and string checking.
Gotchas: Ensure that both parts of the sum do not include the digit '0', and correctly convert numbers to strings for the check.