Program Logic for Sentinel-Controlled Repetition vs. Counter-Controlled Repetition
Compare the program logic for sentinel-controlled repetition with that for counter-controlled repetition in Fig. 4.7. In counter-controlled repetition, each iteration of the
while statement (lines 49–56 of Fig. 4.7) reads a value from the user, for the specified number of iterations. In sentinel-controlled repetition, the program reads the first value (lines 51–53 of Fig. 4.10) before reaching the
while. This value determines whether the program’s flow of control should enter the body of the
while. If the condition is false, the user entered the sentinel value, so the body does not execute (i.e., no grades were entered). If, on the other hand, the condition is ...