There's more than one way to do it

[binarym@trait-plat]:~% cat test.pl
#!/usr/bin/perl

while(<STDIN>){
while(/(top|left|x|y)(:|=)(\d+)/g){ print "1ドル => 3ドル\n"; }
}
[binarym@trait-plat]:~% cat file
< a class="plop" style="top:50px; left:60px" href="plip.php?x=10&y=50" >< img src='img/1.png'/ >< /a >

[binarym@trait-plat]:~% cat file| perl test.pl
top => 50
left => 60
x => 10
y => 50
[binarym@trait-plat]:~%