QPBO:实现了基于屋顶对偶性的最小化具有一元和成对项的二元变量函数的算法

QPBO 基于以下论文中描述的屋顶对偶性，实现了用于最小化具有一元和成对项的二元变量函数的算法： Roof duality, complementation and persistency in quadratic 0-1 optimization. P. L. Hammer, P. Hansen, and B. Simeone. Mathematical Programming, 28:121-155, 1984. Network flows and minimization of quadratic pseudo-Boolean functions. E. Boros, P. L. Hammer, and X. Sun. Technical Report RRR 17-1991, RUTCOR Research Report, May 1991. Preprocessing of