C++ Class 2: A Simple Program (Continued)

A Simple Program (Continued)

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Output of the above program:

Another Example:

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Output of the above program:

Another Simple Program:

Adding Two Integers:

• Variables
• Location in memory where value can be stored
• Fundamental data types
• int - integer numbers (whole numbers + and -)
• char - characters
• float/double - floating point numbers
• Declare variables with name and data type before use

int integer1;
int integer2;
int sum;

• Can declare several variables of same type in one declaration
• comma-separated list

                         

int integer1, integer2, sum;

• Variable names
• Valid identifier
• Series of characters (letters, digits, underscores)
• Cannot begin with digit
• Case sensitive
• Input stream object
• >> (stream extraction operator)
• used with cin
• Waits for user to input value, then press Enter (Return) key
• Stores value in variable to right of operator
• Coverts value to variable data type
• = (assignment operator)
• Assigns value to variable
• Binary operator (works on two operands)
• Example:
• sum = variable1 + variable2;
• Operands : sum, value of expression, variable1+variable2

Code:

// http://welearncpp.blogspot.com
// code3.cpp
// Addition Program
#include <iostream>
using namespace std;

// function main begins execution of program
int main()

{
 int integer1; // first number to be input by user
 int integer2; // second number to be input by user
 int sum; // variable in which sum will be stored

 cout << "Enter first integer: "; // prompt
 cin >> integer1; // read an integer

 cout << "Enter second integer: "; // prompt
 cin >> integer2; // read an integer

 sum = integer1 + integer2; // assign result to sum

 cout << "Sum is " << sum << endl; // print sum
 
 return 0; // indicates successfull execution of program
} // ends the main function

Output of the above program:

Well after this class you might be able to create simple programs such as simple calculator. We will soon come back with a new class for new things..

For complete list of manipulators visit this site:
http://www.cplusplus.com/reference/library/manipulators/