Practise: Simple Colouring
This verified teaching position begins directly with a real Simple Colouring pattern. Follow the chain, inspect the candidates and make the deduction before you continue.
You are at the verified key position. Use a hint to follow the chain link by link when you need support.
How to spot it
Pick a digit with many bi-location units. Start anywhere and colour alternately along the strong links. Then check for two same-coloured cells in one unit, and for uncoloured cells that see both colours.
Put it to use
Where you will meet it
Expert grids are the only place this pattern regularly decides the solve. Bring your notes.
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Type the position into the solver and it walks the whole solution, naming the technique behind every step — including this one.
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