Defanging an IP Address

Given a valid (IPv4) IP address, return a defanged version of that IP address.

A defanged IP address replaces every period "." with "[.]".

Example 1:

Input: address = "1.1.1.1"

Output: "1[.]1[.]1[.]1"

Example 2:

Input: address = "255.100.50.0"

Output: "255[.]100[.]50[.]0"

Constraints:

The given address is a valid IPv4 address.

Solution:

using System;
using System.Collections.Generic;
using System.Text;

namespace LeetCode.AskGif.Easy.String
{
 class DefangIPaddrSln
 {
 public void execute()
 {
 var res = DefangIPaddr("255.100.50.0");
 }

 public string DefangIPaddr(string address)
 {
 var str = new StringBuilder();
 for (int i = 0; i < address.Length; i++)
 {
 if (address[i] == '.')
 {
 str.Append("[.]");
 }
 else
 {
 str.Append(address[i]);
 }
 }
 return str.ToString();
 }
 }
}

Time Complexity: O(n) - for one traversal

Space Complexity: O(n) - Construction of StringBuilder