The game is based on the well known MasterMind.
However, in DigitMind instead of colors one has to guess a code of 4 different digits out of a set that depends on the difficulty level.
DigitMind implements two game types that differ in the way the program determines the score. For the score-type: 'position' the program determines how many digits that are part of the code and at the correct position and how many are part of the code but placed at the wrong position. For the score-type 'difference' the program determines for each position the absolute difference (for example 3-8=5) between the digits in the guess and those in the code and then sums them all which gives the score.
Using the scores, the player has to guess the code within 9 turns. Especially for the 'difference' score-type this will be a challenge at the higher levels!