For a number of years I have been familiar with the observation that the quality of programmers is a decreasing function of the density of go to statements in the programs they produce. More recently I discovered why the use of the go to statement has such disastrous effects, and I became convinced that the go to statement should be abolished from all "higher level" programming languages … — E. W. Dijkstra, “Go To Statement Considered Harmful”, CACM, 1968

For this unit, work through the following preparatory activities.