Choosing a Loop Control Structure

If you know how many times a loop is to occur, use a for loop. Problems that require execution of a pre-determined number of loops should be solved with a for statement.

See Handout A12.1, Programming Pointers

The key difference between a while and do-while loop is the location of the boundary condition. In a while loop, the boundary condition is located at the top of the loop. Potentially, the statements within a while loop could happen zero times. If it is possible for the algorithm to occur zero times, use a while loop.

Because a do-while loop has its boundary condition at the bottom of the loop, the loop body must occur at least once. If the nature of the problem being solved requires at least one pass through the loop, use a do-while loop.