1. CS-103 COMPUTER PROGRAMMING
LECTURE 1
Hafiza Maria Maqsood
FAST NU – CHINIOT FSD campus
Hafiza Maria Maqsood, FAST-NU, Chiniot - FSD Campus

2. Tentative Evaluation Breakdown
Assignments 10
Quizzes 20
Project 5
Sessional - 1
12.5
Sessional - 11
Final 40
Note: The evaluation Breakdown plus course outline for all sections will be same
Grading will be combined so don’t rely on your class position look for the batch position
Hafiza Maria Maqsood, FAST-NU, Chiniot - FSD Campus

3. Text Books
“Object Oriented Programming in C++”, Author (s): Robert Lafore.
“C++ How to program”, Author (s): M. Deitel & Dietel.
“Turbo C Programming”, Author (s): Robert Lafore.
Hafiza Maria Maqsood, FAST-NU, Chiniot - FSD Campus

4. Making Software Load into memory and start execution Problem
Executable file
Develop Algorithm
Compile the code
Express Algorithm in the form of pseudo code or flow chart
Write algorithm in C/C++/Java … Language
Writing code in “C++” language means, we must have to follow a certain rules of “C++” language.
This is called syntax of “C++” language.
Hafiza Maria Maqsood, FAST-NU, Chiniot - FSD Campus

5. Making Software Load into memory and start execution Compiler
“Turbo C” in DOS
“gcc” or “g++” in Linux
“Visual C++” in windows
“Borland” in DOS/Windows.
Problem
Executable file
Develop Algorithm
Compile the code
Express Algorithm in the form of pseudo code or flow chart
Write algorithm in C/C++/Java … Language
Writing code in “C++” language means, we must have to follow a certain rules of “C++” language.
This is called syntax of “C++” language.
Hafiza Maria Maqsood, FAST-NU, Chiniot - FSD Campus

6. Basics of a Typical C++ Environment
Loader
Primary
Memory
Program is created in
the editor and stored
on disk.
Preprocessor program
processes the code.
Loader puts program
in memory.
CPU takes each
instruction and
executes it, possibly
storing new data
values as the program
executes.
Compiler
Compiler creates
object code and stores
it on disk.
Linker links the object
code with the libraries,
creates a.out and
stores it on disk
Editor
Preprocessor
Linker
CPU .
Disk
Phases of C++ Programs:
Edit
Preprocess
Compile
Link
Load
Execute
Hafiza Maria Maqsood, FAST-NU, Chiniot - FSD Campus

7. 2 // A first program in C++
1 // Fig. 1.2: fig01_02.cpp
2 // A first program in C++
3 #include <iostream> 4
5 int main()
6 {
7 std::cout << "Welcome to C++!\n"; 8
9 return 0; // indicate that program ended successfully
10 }
Comments
Written between /* and */ or following a //.
Improve program readability and do not cause the computer to perform any action.
preprocessor directive
Message to the C++ preprocessor.
Lines beginning with # are preprocessor directives.
#include <iostream> tells the preprocessor to include the contents of the file <iostream>, which includes input/output operations (such as printing to the screen).
C++ programs contain one or more functions, one of which must be main
Parenthesis are used to indicate a function
int means that main "returns" an integer value. More in Chapter 3.
A left brace { begins the body of every function and a right brace } ends it.
Prints the string of characters contained between the quotation marks.
The entire line, including std::cout, the << operator, the string "Welcome to C++!\n" and the semicolon (;), is called a statement.
All statements must end with a semicolon.
return is a way to exit a function from a function.
return 0, in this case, means that the program terminated normally.
Welcome to C++!
Hafiza Maria Maqsood, FAST-NU, Chiniot - FSD Campus

8. A Simple Program: Printing a Line of Text
std::cout
Standard output stream object
“Connected” to the screen
std:: specifies the "namespace" which cout belongs to
std:: can be removed through the use of using statements
<<
Stream insertion operator
Value to the right of the operator (right operand) inserted into output stream (which is connected to the screen)
std::cout << “Welcome to C++!\n”; \
Escape character
Indicates that a “special” character is to be output

9. A Simple Program: Printing a Line of Text

10. File Handling stream - a sequence of characters interactive (iostream)
 cin - input stream associated with keyboard.
 cout - output stream associated with display.
file (fstream)
 ifstream - defines new input stream (normally associated with a file).
 ofstream - defines new output stream (normally associated with a file).
Hafiza Maria Maqsood, FAST-NU, Chiniot - FSD Campus

11. To access file handling routines:
#include <fstream.h>
2: To declare variables that can be used to access file:
ifstream in_stream;
ofstream out_stream;
3: To connect your program's variable (its internal name) to an external file :
in_stream.open("infile.txt");
out_stream.open("outfile.txt");
4: To see if the file opened successfully:
if (in_stream.fail())
{ cout << "Input file open failed\n";
exit(1); // requires <stdlib.h>}

12. To get data from a file (one option), must declare a variable to hold the data and then read it using the extraction operator:
int num;
in_stream >> num;
[Compare: cin >> num;]
6: To put data into a file, use insertion operator:
out_stream << num;
[Compare: cout << num;]
NOTE: Streams are sequential – data is read and written in order – generally can't back up.
7: When done with the file:
in_stream.close();
out_stream.close();

13. File Modes Name Description ios::in Open file to read ios::out
Open file to write
ios::app
All the date you write, is put at the end of the file. It calls ios::out
ios::ate
All the date you write, is put at the end of the file. It does not call ios::out
ios::trunc
Deletes all previous content in the file. (empties the file)
ios::nocreate
If the file does not exist, opening it with the open() function gets impossible.
ios::noreplace
If the file exists, trying to open it with the open() function, returns an error.

14. File I/O Example: Writing
#include <fstream>
using namespace std;
int main(void) {
ofstream outFile(“fout.txt");
outFile << "Hello World!";
outFile.close();
return 0; }

15. File I/O Example: Reading
#include <iostream>
#include <fstream>
int main(void) {
ifstream openFile(“data.txt"); //open a text file data.txt
char ch;
while(!OpenFile.eof())
OpenFile.get(ch);
cout << ch; }
OpenFile.close();
return 0;

16. File I/O Example: Reading
#include <iostream>
#include <fstream>
#include <string>
int main(void) {
ifstream openFile(“data.txt"); //open a text file data.txt
string line;
if(openFile.is_open()){ //
while(!openFile.eof()){
getline(openFile,line);//read a line from data.txt and put it in a string
cout << line; }
else{
cout<<“File does not exist!”<<endl;
exit(1);}
openFile.close();
return 0;