In this app, he computer will generate a two-digit number between 22 and 99 and you can see in the 16 boxes there will be 28 possible combinations where the boxes will add up to the given number.
In Easy level, you need to fill the A, B, C, and D boxes to complete the Magic Square.
At the Normal level, you need to fill 8 boxes to get the sum of the target.
At the Hard level, you have to fill all the boxes to get the sum of the target value.