Randomized search with hard constraints
The solver randomizes student and seat search order using the browser’s secure random integers, then searches for a placement satisfying the rules. With constraints, the resulting charts are not promised to be uniformly distributed over every feasible arrangement. Regenerating can repeat a chart or give a student the same place again. There is no historical rotation, automatic fairness score, or guarantee of equal time near the board across lessons. Decide any recurring classroom policy separately before using the draw.