Draw the loop connecting the dots. Each number determines, along how many borders of this cell the loop sould appear (e.g. 0 means, that the loop doesn't appear at any border of this cell, 1 - the loop should appear only at one border of this cell, and so on). The loop can't cross itself, break off, nor touch itself with a corner. The loop can be only one. Every puzzle has exactly one and only one solution.

Example:

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