Object-Oriented Programming
B.Sc. Programme in Electrical and Computer Engineering

C++ Basics
Roman Podraza
Institute of Computer Science Warsaw University of Technology

Project is co-financed by European Union within European Social Fund

What Is OOP ?
• Object-oriented programming (OOP) is a currently popular and powerful programming technique • Main characteristics of OOP:
– Encapsulation: a form of information hiding. – Inheritance: code reusability, refinement of ideas. – Polymorphism: multiple meanings in the context of inheritance.

• Origins of C++
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A Sample Program in C++
// The first program in C++ #include using namespace std; int main () { cout 0 ) ; else x *= 3; // quite often // a block is used

// // // // //

e.g. empty statement keyword (optional) statement executed if boolean expression is false
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Instructions
– Multiway if-else statement if (x > 0 && x < 10) x += 10; else if (x >= 10 && x < 20) x += 20; else if (x >= 20 && x < 30) x += 30; else if (x >= 30 && x < 40) x += 40; else x += 100;
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Instructions if (x > 0) if (y > 2) x -= y; else x += y; if (x > 0) { if (y > 2) x -= y; } else x += y;
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Instructions
• switch statement controlling expression

switch ( ch ){ case (’A’): cout name == 0) // a new string (not found in the array) { res->name = new char[strlen(p) + 1]; strcpy (res->name, p); res->val = 0; } return res->val; }

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References int main(){ const int MAX = 256; char buf[MAX]; while (cin>>buf) value(buf)++; // read a word from standard input to buf // value (buf) = value (buf) + 1

for (int i = 0; i < LARGE && vec[i].name != NULL; i++) cout