上海交通大学交大密西根 联合学院·一 ■ UM-SJTU Joint Institute University of Michigan Shanghal Jiao Tong University What is and what is not? Recursion is a solution technique in which large problems are solved by reducing them to smaller problems of the same form. ● Notice:the italicized phrase is crucial to the definition.Otherwise it describes the basic strategy of stepwise refinement.Both strategies involve decomposition. What makes recursion special is that the sub- problems in a recursive form have the same form as the original while stepwise refinement is not.What is and what is not? What is and what is not? • Recursion is a solution technique in which large problems are solved by reducing them to smaller problems of the same form . • Notice: the italicized phrase is crucial to the definition. Otherwise it describes the basic strategy of stepwise refinement. Both strategies involve decomposition. • What makes recursion special is that the sub￾problems in a recursive form have the same form as the original while stepwise refinement is not