A Level Computer Science OCR Practice Exam

What is a count controlled loop?

1. A loop that runs indefinitely until a stop command is given

2. A loop that runs for a fixed number of times

3. A loop that is defined by user input

4. A loop that processes data continuously

The correct answer is: A loop that runs for a fixed number of times

A count-controlled loop is designed to execute a specific number of times, determined prior to the beginning of the loop. This means that the number of iterations is known and predetermined based on a given count, which could be defined by an integer value. The loop typically uses a counter variable to keep track of how many times it has executed. For example, a loop that iterates from 1 to 10 will run exactly 10 times, incrementing the counter by one with each iteration. This type of loop is useful when the exact number of iterations is known in advance, making it simpler to manage compared to other types of loops that rely on conditions or user input. In contrast, loops that run indefinitely, based on stop commands, take their execution from conditions rather than a fixed count; those defined by user input may be more variable and cannot guarantee a predetermined number of iterations. Continuous data processing loops often involve running until certain conditions are met rather than for a set number of times. Therefore, the defining characteristic of a count-controlled loop is its execution for a specified and fixed number of iterations, which aligns perfectly with the solution provided.