#use strict #use warning open(IN1, "tmp01") || die "Cannot open this file"; @lines = ; $i = 0; for (@lines) { $lines[$i]=~s/\s\s+/\t0\t/g; $thislines[$i]=$lines[$i]; print $thislines[$i]; $i++; } open(OUT, ">tmp02") || die "Cannot open this file"; for $thisline(@thislines){ print OUT $thisline;} close(OUT); close(IN1);