Logic Masters Deutschland e.V.

The figure below belongs to a hitori puzzle with unique solution. But my friend erased 3 digits and wrote the letters A, B and C instead of them. He also give the following hints about the letters:

** A, B and C stand for different digits.

** All A, B and C are less than 5.

** C is the arithmetic mean of A and B.

Reconstruct the hitori puzzle with unique solution and solve for it. Here are the rules of the hitori:

Shade some squares so that the numbers don’t appear in a row or column more than once. In addition, shaded squares must not touch each other vertically or horizontally while all un-shaded squares must create a single continuous area.