What happens if a bubble is hit from different directions at the same time? Imagine a situation like this:

1   2   1

    2

1   1   1
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The player clicks on the middle 1 at the bottom.

1   2   1

    2
    ^
1 < 0 > 1
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_

1   2   1

    1
^       ^
0 >   < 0
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_

0 > 2 < 0
v       v
    1
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Does the 2 become 1 or 0?

Update: Also, what happens in the following scenario?

    1 < 0 > 1 
        v     
3   1       1   3
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_

  < 0 >   < 0 >
    v       v
3   1       1   3
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_

3 < 0 >    < 0 > 3
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What happens next? Do the shrapnels explode when they meet each other in the middle?