← All puzzles

Kode #54: hints & solution

Here's the clue board for Kode #54. Start with the spoiler-free hints. If you're still stuck, the full step-by-step solution is below, hidden until you open it.

The clue board

Each row is a guess that's already been graded. ▲ means a right digit in the right spot; ● means a right digit in the wrong spot.

  • 18256▲1●1
  • 28205▲0●2
  • 32079▲0●2
  • 43476▲0●2
  • 50841▲0●0

Spoiler-free hints

  • Exactly one of the four digits is even.
  • The four digits add up to 17.
  • 2 of the digits are 5 or higher.

Try the hints first. The solution below walks through every deduction.

Step-by-step solution

Every Kode can be cracked by pure deduction, with no guessing. This board falls in 9 logical steps. Open the solution to follow them one at a time.

Show the solution · reveals the code

When a row "rules out" a position, it shows that digit there but its ▲ marks are already used up (or it has none), so the digit can't sit there.

  1. Row 5 (0 8 4 1) has no marks at all, so 0, 8, 4, and 1 are not in the code.
  2. Row 2 (8 2 0 5) has 2 marks still unexplained, and only 2 digits are left undecided: 2 and 5. So both are in the code.
  3. Row 1 (8 2 5 6) has 2 marks, already accounted for by 2 and 5. That rules out 6.
  4. Row 4 (3 4 7 6) has 2 marks still unexplained, and only 2 digits are left undecided: 3 and 7. So both are in the code.
  5. Row 3 (2 0 7 9) has 2 marks, already accounted for by 2 and 7. That rules out 9.
  6. Row 1 (8 2 5 6) has one digit in the right spot. Since row 2 rules out the 2 in position 2, it has to be the 5 in position 3.
  7. The 2 has only one spot left: position 4 (row 3 rules out position 1, row 2 rules out position 2, and position 3 is already 5).
  8. The 3 has only one spot left: position 2 (row 4 rules out position 1, position 3 is already 5, and position 4 is already 2).
  9. That leaves the 7 for position 1.

That cracks it: the code is 7352.

Play today's Kode