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# #193 Valid Phone Numbers

單純練習 regex

[LeetCode](https://leetcode.com/problems/valid-phone-numbers/)

```
Given a text file file.txt that contains list of phone numbers (one per line), 
write a one liner bash script to print all valid phone numbers.

You may assume that a valid phone number must appear 
in one of the following two formats: (xxx) xxx-xxxx or xxx-xxx-xxxx. (x means a digit)

You may also assume each line in the text file must not contain leading or trailing white spaces.

input: list of phone numbers (one per line)
output: valid phone (xxx) xxx-xxxx or xxx-xxx-xxxx

```

```
Example:

Assume that file.txt has the following content:

987-123-4567
123 456 7890
(123) 456-7890
Your script should output the following valid phone numbers:

987-123-4567
(123) 456-7890
```

### Edge Case

* 只有數字？
* 前面沒有空格

### 怎麼解

這題是 bash ，自己把它變成判斷是否 valid

```
var validPhone = function(num) {
    let re = /[\(]*\d{3}[\)]*[ -]\d{3}-\d{4}/
    return num.search(re);
};

console.log(validPhone("987-123-4567"))
console.log(validPhone("(123) 456-7890"))
```