DAG Cycle Detector
Valid - part of a DAG
In a cycle - no start point
Dashed - transitive edge
Valid DAG
Graph status
This is a valid DAG. Follow the arrows backward to find where a learner can start: Counting has no prerequisites.
How to use
  • Arrows point from a concept to what it depends on.
  • Click Add cycle-forming edge to break the DAG.
  • Watch which nodes turn red and read why sequencing fails.