Wiki source code of ROS Crash Course

Version 1.1 by Leon Poon on 2021/08/23 10:50
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Leon Poon 1.1 1 = C++ Crash Crash Course =
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3 == Day 1 ==
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5 main function
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7 g++ source1.cpp -o program1
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9 Paths, . and .. in navigating directories
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11 data type - memory, binary
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13 declare variables (int, char, string as series of chars)
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15 statements end with semicolon
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17 cstdio library include
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19 calling a function - printf
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21 if condition block else block (example: do something different based on argc)
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23 for loop - 3 statements (initialiser, condition, post-loop advancement) and a code block
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25 Homework: study "while" loop and "switch" statement
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27 == Day 2 ==
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29 While loop - condition and 1 code block.
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31 Do while loop - code block then condition.
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33 While loop = for loop with empty initialiser/advancement statements
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35 Switch - match expression's result to case label
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37 Switch vs if-else differences.
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39 your own function
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41 calling with parameters copied as separate set of var values in function
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43 classes as blueprints.
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45 complex var data type - instances of a class all have the same set of fields
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47 the "." field accessor (var1.func1() etc)
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49 each instance have it's own separate memory for storing data.
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51 Example code - fibonacci sequence.
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53 Value overflow because not enough number of bits to represent large numbers.
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55 Homework: implement factorial (1 to 20) calculator
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57 == Day 3 ==
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59 factorial printer - 2 approaches:
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61 1. for-loop that goes 1 to 20 and each loop calls fact(n) function and prints return.
62 1. for-loop that goes 1 to 20 and multiplies once each time and print.
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64 set initial values of vars when declaring otherwise initial values are unpredictable
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