I am trying to use unshift with two dimensional arrays but have some peculiear reference thing going on? 
@a=([0,1,2]);
@b=([-1,-2,-3]);


unshift @a,1;
$a[0][0]=4;
$a[0][1]=5;
$a[0][2]=6;


unshift (@b,1);
$b[0][0]=7;
$b[0][1]=8;
$b[0][2]=9;

print $a[0][2];
print $a[1][2];
print $b[0][2];
print $b[1][2];

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running this code gives 9 2 9 -3.
I would expect 6 2 9 -3
Why is the redefining of @b changing the values in @a??

In reply to unshift with two-dimensional arrays by eatthatquestion

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