yapısal programlama yüksek düzeyli dillerin gelişim süreci –1954-1957, fortran (by ibm), for...
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Yapısal Programlama• Yüksek Düzeyli Dillerin Gelişim Süreci
– 1954-1957, Fortran (by IBM), for creating scientific and engineering applications, first commercial high-level programming lang.
– 1959, Cobol, Commercial applications requiring manipulation of large amounts of data
– Late 1960s, Pascal, for academic use
– 1967, BCPL, for writing OSs, software, compilers– 1970, B, early versions of UNIX– 1973, C, UNIX, major operating systems– 1975, BASIC– 1980s, C++, object-oriented programming (OOP)– 1995, Java, create dynamic content for Web pages and for consumer
devices– 2000, C#, designed specifically for the .NET platform
list of directions given to you when you ask
how to get to the local grocery store 1. First, go to steps 8 and 9.2. Drive one mile straight.3. Drive one mile straight again.4. Drive one mile straight again. You
will see the store on your right.5. If the store is closed, go to step
11.6. Stop and get out of your car.7. Go to step 13.8. Drive straight to Harvard Avenue.9. Turn right at 51st Street.10.Go to step 2.11.Turn left on Yale Street.12.Go four miles straight and you will
see another grocery on your left.13.Go in and shop.
1. Drive straight to Harvard Avenue.2. Turn right at 51st Street.3. For the next three miles, keep
driving straight. You will see the grocery on your right.
4. If the grocery is open, go inside.5. If the grocery is closed, turn left on
Yale Street. Go four miles straight and you will see another grocery on your left.
6. Go inside whichever grocery is open and buy groceries.
Benefits of Structure
• Less code equals more power
• Make the code easier to read and follow
• Enable you to break your code into logical parts
• Make it easier to spot where errors are
• Make reusing code easier
The Constructs of Structured Programming
• Sequence (Sıra)• Decision (Karar) (also called selection)• Looping (Döngü) (also called repetition or iteration)
• As long as a programming language supports these three constructs, you can write structured programs.
• An unstructured program contains lots of branching.
Sequence
Decision
Looping
Structured Programming = Yapısal Programlama
• Input Process Output
Sequence (Functions)
Decision (Conditionals)
Looping (Loops)
Basic C++ Code Structure
// C++ code template comment
#include <iostream.h> header file (support for inputs and
outputs)
#include <string.h> header file (support for string handling)
void main() a function
{
// Code goes here!!!!
}
Functions
• Functions are the basic subdivision of code.
• Just as statements are the equivalent of sentences, functions are the equivalent of paragraphs.
• To move between functions you use calls.
Functions
• Main function– Functions called main have a special meaning in C++,
they are functions that will be automatically run.
// C++ code template#include <iostream.h>void main()
{cout << "Hello, World!" << endl;
}
Statement
cout instruction<< insertion operator"Hello, World!" string to be displayed<< insertion operatorendl insert a new line; statement closing
cout << "Hello, World!" << endl;
a function can do more than one thing
// C++ code template
#include <iostream.h>
void main()
{
cout << "Hello, World!" << endl;
cout << "How are you?" << endl;
}
More functions#include <iostream.h>
void hello(){
cout << "Hello, World!" << endl;}
void hello2(){
cout << "Hello, World, MK II!" << endl;}
void main(){
cout << "main function" << endl;}
#include <iostream.h>
void hello(){
cout << "Hello, World!" << endl;}
void hello2(){
cout << "Hello, World, MK II!" << endl;}
void main(){
cout << "main function" << endl;hello();hello2;
}
Remember to have the function appear before you call it
#include <iostream.h>
void hello(){
cout << "Hello, World!" << endl;hello2();
}
void hello2(){
cout << "Hello, World, MK II!" << endl;}
void main(){
cout << "main function" << endl;hello();
}
3 Örneği inceleyiniz. Yanlış olanlar ne?
#include <iostream.h>
void hello(){
cout << "main function" << endl;}
void main(){
cout << "main function" << endl;}
#include <iostream.h>
void main(){
cout << "main function" << endl;hello();hello2();
}
void hello(){
cout << "Hello, World!" << endl;hello2();
}
void hello2(){
cout << "Hello, World, MK II!" << endl;}
Conditionals (Karar yapıları, şartlı yapılar)
• Conditionals revolve around answers to questions. – true/ false– yes/ no
• For breakfast, would you rather have toast or cereal?– Toast– Cereal– Toast & Cereal– None
• Conditionals revolve around making a decision
Conditionals in C++
if (condition)
{
// do statements here if the condition is true
}
else
{
// do these statements if the condition is false
};
Loops (Döngü yapıları)
• the same piece of code a number of times– Bir komutun (ya da komut bloğunun) belirli
sayıda işletilmesi– Bir komutun (ya da komut bloğunun) belirli bir
şart gerçekleştiği sürece (bir ön teste bağlı olarak) işletilmesi
– Bir komutun (ya da komut bloğunun) belirli bir şart gerçekleşene kadar (bir son teste bağlı olarak) işletilmesi
Bir komutun (ya da komut bloğunun) belirli sayıda işletilmesi
C++ “for” yapısı: Örnek 1
for ( <initialisation> ; <terminating condition> ; <increment> ){
// statement (or block of statements)
}
C++ “for” yapısı: Örnek 2
Bir komutun (ya da komut bloğunun) belirli bir şart gerçekleştiği sürece (bir ön teste bağlı olarak) işletilmesi
C++ “while” yapısı
Bir komutun (ya da komut bloğunun) belirli bir şart gerçekleşene kadar (bir son teste bağlı olarak) işletilmesi
C++ “do while” yapısı
Infinite Loops