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Two-String Kite

When a row string and a column string meet through one box.

Explanation

A Two-String Kite uses one conjugate pair in a row and one conjugate pair in a column for the same candidate. If one end of each pair sits in the same box, the two outer endpoints force one of them to contain that candidate, so any cell seeing both endpoints can remove it.

Two-String Kite example Sudoku board 2 8 9 3 8 7 4 2 4 2 3 9 8 5 1 6 5 7 3 4 9 8 8 9 6 5 1 7 4 9 8 2 3 6 5 7 2 6 8 6 4 8 3 5 2 9 8 7 2 1 6 3 5
An example board where Two-String Kite applies

Practice tip

Scan one candidate at a time. Find row pairs and column pairs first, then check whether one end of each pair links inside the same box.

Example steps

  1. Find a row where the candidate appears in exactly two cells.
  2. Find a column where the same candidate appears in exactly two cells.
  3. Use the linked box to remove the candidate from cells that see both outer endpoints.

Try this technique on a real puzzle.

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