A-level COMPUTER SCIENCE Paper 1 June 2021

Preliminary Material To be opened and issued to candidates on or after 1 September 2020, subject to the instructions given in the Teachers’ Notes (7517/1/TN). Note • The Preliminary Material and Skeleton Program are to be seen by candidates and their teachers only, for use during preparation for the examination on Tuesday 8 June 2021. It cannot be used by anyone else for any other purpose, other than that stated in the instructions issued, until after the examination date has passed. It must not be provided to third parties. Information • A Skeleton Program is provided separately by your teacher and must be read in conjunction with this Preliminary Material. • You are advised to familiarise yourselves with the Preliminary Material and Skeleton Program before the examination. • A copy of this Preliminary Material and the Skeleton Program will be made available to you in hard copy and electronically at the start of the examination. • You must not take any copy of the Preliminary Material, Skeleton Program or any other material into the examination room. A-level COMPUTER SCIENCE Paper 1 June 2021 2 IB/G/Jun21/7517/1/PM There is no Preliminary Material printed on this page 3 IB/G/Jun21/7517/1/PM Turn over ► INSTRUCTIONS FOR CANDIDATES Electronic Answer Document Answers for all questions, for all sections, must be entered into the word-processed document made available to you at the start of the examination and referred to in the question paper rubrics as the Electronic Answer Document. Preparation for the Examination You should ensure that you are familiar with the Preliminary Material and the Skeleton Program for your programming language. Data File A Data File named is supplied with the Skeleton Program. 4 IB/G/Jun21/7517/1/PM Hex Baron Hex Baron is a two-player game in which players issue commands to control pieces on a grid of hexagonal tiles. The winner is the player who has the most victory points (VPs) at the end of the game. When it is a player’s turn they give a series of three commands. Once all three commands have been given the program attempts to execute each command, in the order they were given. If an illegal command is given then that command will not be executed, but other commands given by the player will still be executed if they are legal. To successfully execute a command some of the resources in a player’s supply might need to be used (lumber, fuel and spare pieces). The five available commands are: • move, used to move a piece from one tile to another • upgrade, used to change a piece into another type of piece • spawn, used to create a new piece • saw, used to obtain lumber • dig, used to obtain fuel. Each tile: • has an ID • has a type of terrain • has (x, y, z) coordinates • is either empty or contains a piece. The different types of terrain are: • forest (represented by the # symbol) • peat bog (represented by the ~ symbol) • field (represented by a space). In the default game there is a grid size of 8, which means that there are 32 tiles in the grid. Each tile is stored in a list and the position (index) of the tile in the list is used to identify it. The coordinates of the tile are sometimes used by the program, for example, when calculating the distance between two tiles.