A program stores data in a text file. When data is read from the file, it is placed in a queue. (a) The diagram below represents an Abstract Data Type (ADT) implementation of the queue. Each data item is stored in a separate location in the data structure. During initial design, the queue is limited to holding a maximum of 10 data items. The operation of this queue may be summarised as follows: • The Front of Queue Pointer points to the next data item to be removed. • The End of Queue Pointer points to the last data item added. • The queue is circular so that locations can be reused. [Figure 3.1] (ii) The following diagram shows the state of the queue after several operations have been performed. All queue locations have been used at least once. [Figure 3.2]

1. (a)(i)Describe how the data items Orange and Yellow are added to the queue shown in the diagram.[4]
2. (a)(ii)State the number of data items in the queue.[1]
3. (b)The design of the queue is completed and the number of locations is increased. A function AddToQueue() has been written. It takes a string as a parameter and adds this to the queue. The function will return TRUE if the string was added successfully. A procedure FileToQueue() will add each line from the file to the queue. This procedure will end when all lines have been added or when the queue is full. Describe the algorithm for procedure FileToQueue(). Do not use pseudocode in your answer.[5]

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