construct/nppc three coloring

construct/nppc three coloring: a task in MathConstructOptimize-Envs-harbor (Harbor dataset). Graph with 120 vertices labelled 0..119 and edge list 0, 2 , 0, 7 , 0, 11 , 0, 21 , 0, 69 , 0, 96 , 0, 112 , 1, 19 , 1, 45 , 1, 49 , 1, 94 , 1, 104 , 1, 109 , 1, 113 , 1, 114 , 1, 116 , 2, 33 , 2, 39 , 2…