quadratic assignment problem

例句：

1. 1.The quadratic assignment problem is a common challenge in optimization.
   二次分配问题是优化中常见的挑战。
2. 2.In this study, we focused on the quadratic assignment problem to improve our understanding of the subject.
   在这个研究中，我们专注于二次分配问题，以增进我们对这一主题的理解。
3. 3. The quadratic assignment problem has been studied extensively in economics and operations research.
   在经济学和运筹学中，二次分配问题已经得到了广泛的研究。