title: PHP regex for Lebanese phone number
body: <p>i am writing a php app that asks people for their phone number in lebanon. I don't want to be very strict in the entry format so i'm running into some trouble validating. </p>
  
  <p>A lebanese phone number looks like that.</p>
  
  <p>961 3 123456</p>
  
  <p><strong>961</strong>: the country code. i want it to be valid with or without it.</p>
  
  <p><strong>3</strong>: the area code. here's where it is tricky. the possible area codes are 03, 70 and 71. when the country code is present, 03 drops the 0 and becomes 3 while 70 and 71 are as is with or without country code. </p>
  
  <p><strong>123456</strong>: the phone number, always 6 digits.</p>
  
  <p>here are the formats i'm trying to validate:</p>
  
  <p>961 3 123456<br>
  961 70 123456<br>
  961 71 123456<br>
  03 123456<br>
  70 123456<br>
  71 123456  </p>
  
  <p>the spaces are here just for the sake of clarity, i am validating after stripping all spaces and non alphanumeric characters.</p>
  
  <p>that's it, would be great if someone can help.
  thanks</p>