Place numbers inside every cell, so that each cell indicates how many different numbers its arrow(s) points to.
The middle arrow on the upper row sees only a single number and should therefore contain a 1. Because the middle arrow on the bottom row sees two different numbers, the center figure can not contain a 1. Because it can be at most a 2, it should be a 2.
The figure in the lower right sees at least two distinct numbers. Because of the arrow in the upper right, it needs to have the same value as his direct upper neighbour, which can be at most a 2. So both will become a 2. As a consequence there will be a 1 in the lower left, and also the remaining arrows become a 1.