Slide 1Slide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12COSC 181 – Foundations of Computer ProgrammingClass 2Goals for TodayFinish Up Chapter 1 – IntroductionStart Chapter 2 – Intro to C++ ProgrammingGo Ahead and Login If you can’t, sit next to someone who canTypical C++ Development1. Edit – actually write the code (labor intensive)2. Preprocess – handle compiler directives (automatic)text replacement, outside compilations (if any)3. Compile – create object code and store on disk4. Link – connect with necessary external resources (libraries, etc.) & store executable (machine code)5. Load – put program in main memory (really a function of the operating system)6. Execute – central processing unit (processor) performs each individual machine instruction and updates/stores data when/where indicatedFailing To RunComputers are superbly literal and always do only what they are instructed to and no moreIf instructions cannot be completed as given then the program will fail to run (cause an error)Run-time vs Compile-time errorsGood Programming Practices1. Keep it Simplefind the most straightforward solution2. Read the Documentation3. Make use of the resources available to you4. DON’T get frustrated5. DON’T be scared to experimentbuild your knowledge base as you go6. DON’T be forced to hurryIntroduction to C++// Fig. 2.1: fig02_01.cpp// Text-printing program.#include <iostream> // allows program to output data to the screen// function main begins program executionint main(){ std::cout << "Welcome to C++!\n"; // display message return 0; // indicate that program ended successfully} // end function mainThese are comments : denoted by “//”Important Components#include<foo>tells the preprocessor to treat the contents of a specified file (foo) as if those contents had appeared in the source program int main(){…}1 or more “functions” for each programEach function does some processing and returns a value (this value may be empty)exactly one function must be called “main”beginning of every C++ programin this case “returns” an integer valuereturn 0;In main() this is the very last statement of a C++ programIn general, it’s the very last statement of any function that its inCould also have said “return 1;” for instancewhite space – used for making code easier to readNote: each statement (command) is ended by a “;” each function is opened by “{“ and closed by “}”certain terms are “keywords” (#include, int, main, return)Have a pre-determined meaningOutputstd::cout << “Welcome to C++!\n”;the line as a whole is a statementstd::cout Standard character output streamOutput in C++ occurs over “streams” The standard stream (above) is connected to the monitor by defaultnamespace :: commandstd is the namespace defined by “iostream” cover namespaces laterOutput Continued“<<“ stream insertion operatorValue on right of << is inserted into the stream which appears on the left of <<“Welcome to C++!\n”Value on the right of the << operator“ ” – denote a literal string\n is a special command called an “escape sequence” that represents “new line” in C++the backslash (“\”) – lets the compiler know that you want to “escape” a character and denote an “escape sequence”See Fig 2.2 in your book for list of escape sequencesDevC++ QuirkinessIf we run the program as entered then we will only see the output for a flashNot long enough to tell what happenedThis is not the case in every development environmentNeed to add an extra line of code to make the program wait for us to dismiss it.Slightly Updated Version// Fig. 2.1: fig02_01.cpp// Text-printing program.#include <iostream> // allows program to output data to the screen// function main begins program executionint main(){ std::cout << "Welcome to C++!\n"; // display message system(“PAUSE”); // prepackaged wait function return 0; // indicate that program ended successfully} // end function mainNow… Try It!Open up DevC++File -> New -> Source FileType in the CodeUnder the “Execute” menu First hit “Compile”Save the code on your DesktopWait for the screen to say Done (0 errors, 0 warnings)Then, under “Execute” menu hit “Run”Congratulations on your first C++ programNow, try and make it say something