This is a classical mini-game called 1A2B for UWP. It is also an interesting math puzzle.
At the start of the game, the app generates a number whit none duplicate digit at length of 4 randomly. Each time you submit a number at the length of 4. The app judge it and give feedback consist that how many digits you guess right but the position is wrong, and how many digits you guess right and the position also right.
Can you solve the problem within 10 attempts?
