When the user wants to assign colors (labels, slots, frequencies) to graph vertices so adjacent vertices differ, minimize the number of colors used, or bound the chromatic number with exact or heuristic methods. Also use when the user mentions "graph coloring," "chromatic number," "DSATUR," "tabucol," "Kempe chains," "coloring conflicts," or when items must share scarce resources subject to pairwise conflicts (exam slots, CPU registers, radio frequencies). For full timetabling models with soft constraints, see timetabling-and-rostering; for CP-SAT modeling depth, see constraint-programming.
