使用perl來編程，有什麽方法能在腳本運行時，對txt文件中某壹行的變量值快速進行修改？

$e=0;

while(<$f>){

if(/cccc =\d+/){}

elsif(/bbbb =\d+){$e=1;}

else{if($e){$d.=$_;}else{$p.=$_;}}

}

close $f;

seek($f,0,0);

@c=(15,10,8);

@b=(12,9,20);

for(1..3){

print "try the $_ times\n";

<STDIN>;

open($f,'a.txt');

print $f $d;

print $f “cccc = ",$c[$_-1],"\nbbbb =”,$b[$_-1],"\n";

print $f $p;

close $f;

}