$#$x will print the last subscript value of the refered array. To find number of contents $#$x has to be $#$x + 1.

Now the subroutine h will be called inside the subroutine j.

sub h {
    my ($x,$y)=@_;
    print "the val of x is $#$x and y is $#$y\n";
}
sub j {
    my ($i, $j, $k)=@_;
    print "\ni am in the function j\n\n";
    &$k($i,$j);
}
@ar = qw/1 2 3 4/;
@vr = qw/56 7 8 9/;

&j (\@ar, \@vr, \&h);
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