Shell Programming and Scripting

 
 awk 'NF==1{$3=$1;$1=L}P&&NF>=3{print $1,$3;L=$1}/^___/{P=1}' FILE

awk 'NF==1{              ##checking condition here if NF(number of fields on current line) is 1 then do following.
            $3=$1;       ##Setting 3rd field value same as 1st field value.
            $1=L}        ##Setting 1st field value as the value of variable L here.
      P&&NF>=3{          ##checking condition here if variable P is NOT NULL and NF is greater OR equal to 3 then do following.
            print $1,$3; ##Printing 1st and 3rd fields values here.
            L=$1}        ##Setting variable L value as $1 of current line.
      /^___/{            ##checking condition here if a line starts with ___ then do following.
            P=1}         ##Setting variable P value to 1 here.
' FILE                   ##Mentioning Input_file name here.