Completeness
"completeness"是search algorithm中一个非常重要的概念，维基百科Search algorithm中对它的解释是：
Unlike general metaheuristics, which at best work only in a probabilistic sense, many of these tree-search methods are guaranteed to find the exact or optimal solution, if given enough time. This is called "completeness".
它并没有给出准确的描述，"completeness"所链接到的是维基百科Completeness (logic)，这篇文章是不易理解的。下面是一些分析：
What is meant by search algorithm completeness?
If an algorithm is complete, it means that if at least one solution exists then the algorithm is guaranteed find a solution in a finite amount of time.