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# # 1108 Defanging an IP Address

[LeetCode](https://leetcode.com/problems/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.
```

### 怎麼解

用 regex replace

```
var defangIPaddr = function(address) {
    let re = /(\.)/g;
    let result = address.replace(re, '[.]');
    return result;
};
console.log(defangIPaddr("1.1.1.1"))
//  faster than 89.16% of JavaScript online submissions 
```