34 lines
1.4 KiB
Markdown
34 lines
1.4 KiB
Markdown
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You prepared the cashier for the step to multiple cashiers. But let's not go there yet.
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First you should flesh out the concept of a customer.
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## Model
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In our model the customer should have a list of items he buys, but you could add more things to make it more interesting.
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For example some customers pack their items painfully slow and some really fast. So let's add that too.
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So the scanning phase takes the amount of time of the item plus the packing-speed.
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## Knowledge
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For that we need a new language construct. The struct.
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A struct works similar to an enum, but instead counting up numbers, you basically packing
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multiple variables together to build more complex data-types.
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Here is an example of a struct for a person:
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typedef struct
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{
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char *Name; // This is some Text
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int Age;
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gender Gender; // This is an enum
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}person;
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If you want to access a member of the struct you write first the name of the variable containing the struct, then a dot and then the name of the member.
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For example we have a variable Bob ``person Bob`` and want to assign him an age of 35 ``Bob.age = 35``.
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Because the file got a little big, we pulled out some of the definitions like the enums into a
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header file and included it with the command `#include "supermarket.h"`.
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## Task
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Your task is to implement a struct for the customer and take the packing speed into account.
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