International Symposium on Computing and Networking Workshops (CANDARW)

Multi-color ordering method for minimizing number of colors in quadratic unconstrained binary optimization formulation

Tomohiro Suzuki

Published Nov 25, 2025• 0 citations

Abstract

The multi-coloring method can be formulated as a graph coloring problem, which is known to be NP-hard. In this study, we solve the graph coloring problem using a quadratic unconstrained binary optimization (QUBO) formulation. We perform parameter tuning and propose an iterative color reduction method to further decrease the number of colors. Finally, we evaluate the effectiveness of the resulting parallel ordering as a preprocessing step for iterative methods, compared with conventional approaches.

DOI: 10.1109/candarw68385.2025.00037

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