09 Sept 2026•Easy•Go / Python / TypeScript

Defanging an IP Address

Replace every period in an IPv4 address with a bracketed period.

Apply a global string replacement from each dot to the required defanged token.

Complexity

O(n) time and O(n) output space.

Go•defanging-an-ip-address/solution.go

package main

import "strings"

func defangIPaddr(address string) string { return strings.ReplaceAll(address, ".", "[.]") }

Python•defanging-an-ip-address/solution.py

class Solution:
    def defangIPaddr(self, address: str) -> str:
        return address.replace(".", "[.]")

TypeScript•defanging-an-ip-address/solution.ts

function defangIPaddr(address: string): string {
  return address.replaceAll(".", "[.]");
}