perl 字符串变量内容替换

#!/usr/bin/perl

$_ = "he is a great scienceist!";

s/he/they/;

print $_;

print "\n";

my $string = "big exists!";

$string =~ s/big/replacementbig/g;

print "string: $string\n";

$tt="fff ddd ddfdgfgfdh gff fff dfdshffh";

$tt=~ s/fff/aaa/g;

print "\n $tt";