[Solved] awk how to parse based on pattern but skip multiple similar lines and accept only single line occurence [closed]

by 


awk '
   /connection from/{ nr=NR; conn[nr]=$NF; auth_counter[nr]=0; next; }
   { auth_counter[nr]++; auth_msg[nr]=$NF; }
   END{
      for(i in auth_counter) if(auth_counter[i]==1) print conn[i], auth_msg[i]  
   }' file

x.x.x.x BBB
y.y.y.x CCC
x.x.x.a ZZZ

solved awk how to parse based on pattern but skip multiple similar lines and accept only single line occurence [closed]