Monkeymore Sudoku

Forcing Net

Level 12 · Black Belt

Prerequisite: ForcingLearn next → Forcing Chains

Overview

Forcing Net extends Forcing Chains by following all implications from each candidate simultaneously, not just single chains. This creates a branching implication network that can find deeper contradictions and common outcomes.

How It Works

  1. Find a cell with multiple candidates.
  2. Assume each candidate in turn and follow ALL resulting implications (not just one chain).
  3. If an assumption leads to a contradiction (impossible state), eliminate that candidate.
  4. If all assumptions force the same conclusion, that conclusion is valid.

Example

Cell r1c1 has 3 candidates: {1, 3, 9}.

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Tips & Patterns

  • Forcing Nets are more powerful than Forcing Chains because they follow every implication, not just one path.
  • They're computationally expensive and are typically a last resort before brute force.
  • The branching nature makes them hard to track by hand.