在管理科学、计算机科学、分子物理学、生物学、超大规模集成电路设计、代码设计、图像处理和电子工程等领域中，存在着大量的组合优化问题。例如，货郎担问题、最大截问题、0—1背包问题、图着色问题、设备布局问题以及布线问题等，这些问题至今仍未找到多项式时间算法。-In management science, computer science, molecular physics, biology, VLSI design, code design, image processing and electronic engineering and other fields, there are a large number of combinatorial optimization problems. For example, the traveling salesman problem, the maximum cut problem ,0-1 knapsack problem, graph coloring problems, equipment problems and wiring layout problems, these problems have yet to find a polynomial time algorithm.