In this chapter, we demonstrated how to develop algorithms using top-down, stepwise refinement. Only three types of control statements—sequence, selection and iteration—are needed to develop any algorithm. Specifically, we demonstrated the if single-selection statement, the if…else double-selection statement and the while iteration statement. We used control-statement stacking to total and compute the average of a set of student grades with counter- and sentinel-controlled iteration, and we used control-statement nesting to analyze and make decisions based on a set of exam results. We introduced C++’s compound assignment operators and its increment and decrement operators. Finally, we discussed why C++’s fundamental types are not portable. In Chapter 5, we continue our discussion of control statements, introducing the for, do…while and switch statements.