BEGIN { f=0 ; prev="" }

length($0) > 1 && substr($0,length($0),1)~/\\/ { prev=prev substr($0,1,length($0)-1); 
                                                 f=1; next }
                                                 
f==1 { t=prev $0; gsub(" +"," ",t); print t; f=0 ; prev=""; next }
{ print $0 }
