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#include

main()

{

printf("Hello World\n");

return 0;

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include

This includes a file called stdio.hwhich lets ususe certain commands.

stdio is short for Standard Input/Output whichmeans it has commands for input like readingfrom the keyboard and output like printing thingson the screen.

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main!

main is the name of the point where the programstarts and the brackets are there for a reason that

you will learn in the future but they ha"e to bethere.

#ll programs must ha"e a main function

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$%

The & curly brackets are used to group all thecommands together so it is known that thecommands belong to main. These curlybrackets are used "ery often in ' to groupthings together.

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printf()ello *orld+n(!,

This is the printf command and it prints te-t on the screen.The data that is to be printed is put inside brackets.

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'omments in a program are called inlinedocumentation

They should be included to e-plain the purposeof the program and describe processing steps

They do not affect how a program works

' comments can take two forms

// this comment runs to the end of the line

/* this comment runs to the terminating

symbol, even across line breaks */

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Spaces0 blank lines0 and tabs are called whitespace

*hite space is used to separate words and

symbols in a program 1-tra white space is ignored

# "alid ' program can be formatted many ways

2rograms should be formatted to enhancereadability0 using consistent indentation

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main() {

#include

// comments about the rogram

rintf(!"ello orld$ %n&)'

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errors

errors

Edit and

sav program

Compil program

Ex cut program and

valuat r sults

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The synta- rulesof a language define how we canput together symbols0 reser"ed words0 andidentifiers to make a "alid program

The semanticsof a program statement define whatthat statement means its purpose or role in aprogram!

# program that is syntactically correct is notnecessarily logically semantically! correct

# program will always do what we tell it to do0 notwhat we meant to tell it to do

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1nd

ddo