How to play

  • The variables represents unique integers ranging from 1 to the number of variables;
  • Multiplication is implicit: AB means A times B, or A * B;
  • Based on the clues (equations and inequations), use the grid to create relations between variables and values:
    • Click once on a square to mark that value as false;
    • Click twice to assign the chosen value to the variable;
    • Click three times to clear the square.
  • The color of a clue changes after you assign values to all of its variables:
    • GREEN means that the statement is true;
    • RED means that the statement is false.
  • Click on a clue to mark it as used;
  • The game ends when all values are correctly assigned to the variables.

Tips

  • Figuring out which variables can't have the lowest or the highest values is a good starting point, e.g, A > B shows that A ≠ 1;
  • Analyzing the hypothetical equation C + D = 4, we can make the following statements:
  • Another quick tip: A = 2B means that A is even;
  • Don't be afraid of using pen and paper. Some puzzles might require it.

More 4x4 puzzles

  • if B ≤ 3 then C ≤ 2
  • if D ≠ 1 then A + B ≤ 4
  • if A + D ≤ 5 then B < 2

Solve

  • C + D ≤ 6 if and only if A > 1
  • D < 1 if and only if B ≤ 2
  • D ≠ 4 if and only if A ≤ 3
  • A + D ≤ 3 if and only if B ≠ 3

Solve

  • A + B ≤ 7 if and only if C + D ≤ 3
  • C < 3 if and only if A ≠ 3
  • A ≠ 2 if and only if D ≤ 1

Solve

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