2 From C to C++Object Orientation -:: General Program Template

2

FROM C TO C++OBJECT ORIENTATION -

2.1

General Program Template #include vs. #include using namespace std; int main(void) { // or int main() definitions/declarations/statements return expr; }

Exercise 2.1 Compile and execute this program printing Hello World on the screen.

2.2

Keywords and Identifiers

❍ Keywords asm bool char continue double except finally goto long operator register signed struct throw typedef unsigned volatile

auto break class default dynamic_cast explicit float if mutable private reinterpret_cast sizeof switch true typeid using while

bad_cast case const delete else extern for inline namespace protected return static template try typename virtual

bad_typeid catch const_cast do enum false friend int new public short static_cast this type_info union void

❍ Alternative operators bitand compl not_eq

and and_eq

cs2260@UMSL 2005 Cezary Z. Janikow

bitor or_eq

or xor_eq

xor not

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2 From C to C++Object Orientation -:: Comments

❍ Do not use identifiers starting with (used for system names) ❍ _ _ letter ❍ _ Letter ❍ Naming standards ❍ variable/object ❍ Class/Type Example 2.1 Naming examples. class Car; class MyCar; int numOfItems; Car myLegend;

2.3

Comments // comment up to eol only /* can also use C style */

2.4

New Console IO

Example 2.2 Illustration of the standard device connection through stream objects. cout:ostream Program cerr:ostream

cin:istream

cs2260@UMSL 2005 Cezary Z. Janikow

Console

Kb

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2 From C to C++Object Orientation -:: Anywhere declaration/definition

❍ cin and cout are buffered ❍ all are formatted ❍ types are automatically detected on compilation ❍ overloaded > for output and input ❍ endl vs. ‘\n’ Example 2.3 > can be chained and the types are detected by the compiler. cout x >> y;

Exercise 2.2 Program to read a number and print it within a string.

2.5

Anywhere declaration/definition ❍ Anywhere before being used but try keeping together ❍ Also inside for loops for (int i=0; i> x) cout