A two-player logic game — you vs the CPU.
Think of a secret number
Pick a 4-digit number where all digits are unique (e.g. 3 8 1 5). No repeats. Keep it secret — the CPU will try to guess it.
Your turn: guess the CPU's number
The CPU has also picked a 4-digit number with unique digits. You go first — enter your guess and get feedback after each attempt.
Understand the feedback
How many digits in the guess exist in the secret number — regardless of position.
Of those correct digits, how many are also in the right position. Always ≤ Correct digits.
Example
CPU's turn: give honest feedback
After your guess, the CPU will guess your number. Compare its guess to your secret and report the correct digits and correct places honestly. It will catch you if you cheat.
First to crack the code wins
Whoever guesses the other's number first wins. Use logic, eliminate possibilities, and don't give up.
The CPU is already judging your strategy.