leetcode 1108. Defanging an IP Address

Seawolf

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"

class Solution {
    public String defangIPaddr(String address) {
        StringBuilder re = new StringBuilder();
        for(int i = 0; i< address.length(); i++){
            char a = address.charAt(i);
            if(a == '.') re.append("[.]");
            else re.append(a);
        }
        
        return re.toString();
    }
}