Sudoku Luna
HardChains and uniqueness

Practise: Simple Colouring

Follow one digit through alternating strong links. The prepared notes form two alternating groups.

The prepared 5-notes form one alternating chain. Follow each two-place link, then find a note that sees one cell from each group; do not place a digit yet.

Example 1 of 4

Practice
Mistakes0Hints0Score3,500Time0:00

Your turn first

Your turn first

Trace the marked 5-links into two alternating groups. Which prepared 5-note sees one cell from each group?

Remember

Simple Coloring follows one digit through two-place strong links. The links split into two alternating groups; a candidate seeing both groups cannot keep that digit.

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