Command to print the phone numbers by making the area code(the first 3 digits of the phone numbers) prominent by surrounding them by parentheses

Question

Note There maybe some records in the file where the Name is missing and only the phone number is there or vice-versa.Such records should be considered as invalid records and should not be displayed in the output .Even should not prink blank line in the output for those records .

Sample input:

Danish 5555551212
3456782
Bulbul 5555551213
Kaloana 5555551214
Tina 6665551215
Cj
Mayuri 6665551216

output:

(555)5551212
(555)5551213
(555)5551214
(666)5551215
(666)5551216

MyCode:

BEGIN {FS=" ";c=0;}
{   
    if(NF>1)
    {
      s[c]=$2;
    c=c+1
    }
}

END{
  for (i=0;i<c;i++)
  {
    print s[i] 
  }

   

}

This is just 1/4th mile I have reached .

Answer 1

Could you please try following. Written and tested in https://ideone.com/ZMnuIp link with shown samples only.

awk '
NF==2 && match($2,/^[0-9]{3}/){
  print "(" substr($2,RSTART,RLENGTH) ")" substr($2,RSTART+RLENGTH)
}
' Input_file

Explanation: Checking condition if NFis 2 means if line has 2 fields AND 2nd field starts with 3 digits then do following. Printing ( then sub-string of 3 digits of 2nd field then printing ) and rest of the line then.