While Loop (Stock Count)

On way to determine how many stocks to process is to ask the user, and then count them as we process.

The algorithm then becomes:

        Initialize the portfolio cost and portfolio value

        get the number of stocks

        while there are more stocks to proccess

              Get the number of shares for the next stock

              Get the selling price for the stock

              Get the purchase price for the stock

              Print the data values for the stock

              Accumulate the portfolio cost for the stock

              Accumulate the portfolio value for the stock

              update the number of stocks remaining

        Compute the profit

        Print the result

In each iteration of the loop we decrement the number of stocks remaining. When the count reaches zero, we're done.

But we still have one problem. The syntax of the while statement only allows one statement as the body of the loop. But we have many steps in the algorithm to perform in each iteration.

We resolve this problem by using a compound statement.

The implementation of this algorithm is in stock4.count.c

Things to notice about this code:

We use a new operator in the while condition:

        while( num_stocks > 0 )

These are called Comparison Operators.