Problem Description
Given a valid IPv4 address, return a defanged version of that IP address by replacing every period "." with "[.]".
Key Insights
- The problem is straightforward: it requires a simple string replacement.
- Since IPv4 addresses have a fixed, small structure, iterating through the string or using built-in string methods will be efficient.
- Edge cases are minimal because the input is guaranteed to be a valid IPv4 address.
Space and Time Complexity
Time Complexity: O(n) where n is the length of the address string. Space Complexity: O(n) for storing the new defanged string.
Solution
The solution can use a built-in string method to replace all occurrences of "." with "[.]" in the provided IP address. This approach is both efficient and clear. In languages without a built-in replace function, a simple iteration over each character and an append operation to a new string can be used. This maintains the same O(n) time complexity. The key data structure used here is the string itself, and the algorithmic approach involves either a single pass through the string or leveraging an optimized library function for string replacement.