Phone numbers in the United States typically consist of 11 digits:

- 1-digit country code

- 3-digit area code

- 3-digit central office or exchange code

- 4-digit subscriber number

A valid example can be:

`+1 (555) 555-1234`

. So, the phone number should start with a

`+1`

, followed by a space and then 3 digits enclosed in parentheses. The last 7 digits are separated by a hyphen after the 3 digits.Given a phone number print,

`The phone is valid`

if the phone is valid, and `Invalid number`

otherwise.Input | Output |

+1 (555) 555-1234 | The phone is valid |

+1 (5a5) 555-1234 | Invalid number |

+1 (55) 555-1234 | Invalid number |