Do you need to look things up by coordinates? Do you need to be able to walk through the grid in order? Do you need to be able to jump to a particular row?

How you want to get your data back is important in determining how you should store it. A simple array of arrays might suit you:

my @arr;
while (my ($x, $y, $beans) = read_grid_cell) {
    push @arr, [$x, $y, $beans];
}
# Or the equivalent map statement, if you like.
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You could certainly print the grid back out later. But if you want to get at certain cells (but not be able to walk through in order), you might need a multi-dimensional hash:

my %hash;
while (my ($x, $y, $beans) = read_grid_cell) {
    $hash{$x}{$y} = $beans;
}
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If you need walkability as well as individual cell access, you would have to combine techniques:

my @beans;
my %grid;
while (my ($x, $y, $beans) = read_grid_cell) {
    push @beans, [$x, $y, $beans];
    $grid{$x}{$y} = $beans;
}
# Now you can walk through @beans, or you can lookup by $x and $y,
# but don't change the beans in either spot, because they're not linke
+d!
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