This document discusses the fundamentals of C++ programming including the structure of C++ programs, keywords, data types, variables, constants, and input/output statements. It provides the code for several sample programs and step-by-step instructions for writing, compiling, and running the programs to practice variable declaration, data types, and basic math operations. The document concludes with exercises to test understanding of concepts covered.
1. F2037 PROGRAMMING FUNDAMENTAL OF C++
LAB 1: VARIABLE, KEYWORD AND DATA TYPES
Objectives
By the end of this lab, students should be able to :
• Describe the structure of C++ programmes
• Write, compile and run simple C++ programmes
• Identify and list keywords
• List and define the various data types
• Define variables and constants
Theory/ Topics
• A program must have the function named main().
• Structure of C++ programmes
o The structure of a simple C++ programme is
similar to the structure of C.
Structure Program
< Comment Entry> // First C++ program
< Preprocessor directives > #include <iostream>
#include <string>
main function int main()
{ {
< declaration stat >; int a;
< C++ Statements >; cout << "Welcome to
} Programming n”;
return 0;
}
Table 1.1 : Structure of C++ Programme
Consider the code in the given program:
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2. F2037 PROGRAMMING FUNDAMENTAL OF C++
1. // is used to comment a single line. In addition to //
symbol, C++ supports /* */ for comment entry
operation. /* */ is used to comment a set of
statements.
2. #include <iostream> includes the header file for
the program.
3. main() is the function where the program is written.
4. int a; is the variable declaration.
5. cout is used to display the output statements.
6. Every statement is terminated with a semi-colon,
similar to C.
• Keywords - have a strict meaning as individual tokens
in C++. They cannot be redefined or used in other
contexts.
• Identifier - Sequence of letters, digits and the special
character "_" which is called an underscore. A letter or
underscore must be the first character of an identifier.
As C++ program is built from C, the C++ compiler supports
all the features of C.
The following are the steps involved in writing, compiling
and executing a C++ program :
1. Open Microsoft Visual C++ and type the program.
2. Save the file with the corresponding extension
(filename.cpp)
3. Compile the program.
4. Build & execute/run the program.
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3. F2037 PROGRAMMING FUNDAMENTAL OF C++
Lab 1A
Procedure :
Step 1: Type the programs given below
Step 2: Compile and run the program. Write the output.
Step 3: Save the program as lab1A.cpp.
The following program finds the sum of two numbers and
displays it.
// Program to add two numbers
#include <iostream>
using namespace std;
void main()
{
int a, b, sum;
a = 5;
b = 2;
sum = a + b;
cout << "The sum is: " << sum << "n";
}
Lab 1B
Procedure :
Step 1: Type the programs given below
Step 2: Compile and run the program. Write the output.
Step 3: Change the statement cout << "The sum is: " <<
sum; in line 9 to cout << "The average is: " << sum/2;
Step 4: Save the program as lab1B.cpp.
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4. F2037 PROGRAMMING FUNDAMENTAL OF C++
// Program to find the average of two numbers
#include <iostream>
using namespace std;
void main()
{
int a, b, sum;
a = 5;
b = 2;
sum = a + b;
cout << "The sum is: " << sum;
}
Lab 1C
Procedure :
Step 1: Type the programs given below
Step 2: Compile and run the program. Write the output.
Step 3: Save the program as lab1C.cpp.
// The following program illustrates variable and
// constant declaration.
#include <iostream>
using namespace std;
const float PI = 3.14;
void main()
{
double radius = 3.0;
double circumference;
circumference = 2 * PI * radius;
cout << "Circumference = " << circumference <<endl;
}
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5. F2037 PROGRAMMING FUNDAMENTAL OF C++
Lab 1D
Procedure :
Step 1: Type the programs given below
Step 2: Compile and run the program. Write the output.
Step 3: Save the program as lab1D.cpp.
// The following program illustrates variable and
// constant declaration.
#include <iostream>
#define PI 3.14
using namespace std;
void main()
{
double radius = 3.0;
double circumference;
circumference = 2 * PI * radius;
cout << "Circumference = " << circumference <<endl;
}
Lab 1E
Procedure :
Step 1: Type the programs given below
Step 2: Compile and run the program. Write the output.
Step 3: Save the program as lab1E.cpp.
Program to show the declaration and initialization of
variables with float, double, char, int and boolean data
type.
#include <iostream>
using namespace std;
void main()
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6. F2037 PROGRAMMING FUNDAMENTAL OF C++
{
char grade = 'F';
float price = 77.01;
double average = 145525.92;
bool boolean_variable = true;
int age = 50;
cout << price <<"t"<< average <<"t"<<grade<<"t"<<
boolean_variable <<"t"<<age<<endl;
}
Lab 1F
Procedure :
Step 1: Type the programs given below
Step 2: Compile and run the program. Write the output.
Step 3: Save the program as lab1F.cpp.
Program to show the declaration and initialization of
variables with string data type.
// my first string
#include <iostream>
#include <string>
using namespace std;
void main ()
{
string mystring = "This is a string";
cout << mystring;
}
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7. F2037 PROGRAMMING FUNDAMENTAL OF C++
LAB EXERCISE
1. Describe the functionality of using
a. #include <string> as Preprocessor directives
b. int main (void) as main function
2. For each statement below, state either variable or
constant and find a suitable variable and constant
name
a. the number of month in a year
b. the sum of x + y if given x = 5 and y = 10
3. Based on IPO chart information below:
a. Declare the variable in C++ by using the
appropriate data type
b. Transform the Algorithm into C++ code
IPO Chart Information
Input Processing Output
Number of late days = 7 Calculate amount Display
Number of late charge = amount
0.2 Algorithm
1. Declare the number
of late days, late
charges and
amount
2. Calculate the
amount by
multiplying the
number of late days
with late charge
3. Display amount
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