reference - regarding usage of arrow notation in perl -

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i've following 2 statements written in perl :

@m1 = ( [1,2,3],[4,5,6],[7,8,9] ); # array of references. $mr = [ [1,2,3],[4,5,6],[7,8,9] ]; # anonymous array. $mr holds reference.

when try print:

print "$m1[0][1]\n"; # statement outputs: 2; expected.  print "$mr->[0][1]\n"; #this statement outputs: 2; expected.  print "$mr[0][1]\n"; #this statement doesn't output anything.

i feel second , third print statements same. however, didn't output third print statement.

can let me know wrong third print statement?

this simple. $mr reference. use arrow operator dereference.

also, if use use warnings; use strict;, have received obvious error message:

global symbol "@mr" requires explicit package name

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