# Techtopz

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# C++ | Multiplication of numbers

First program will directly calculate the multiplication which is not flexible. So the second program is introduced which will let you enter the numbers from keyboard and calculate the multiplication of it. The later programs are modified forms of second program and lets you add more variables to the program and lets you calculate multiplication of more numbers. The same way you can extend your program. Go enjoy the program. Lets begin……

First program

``````#include<iostream.h>
#include<conio.h>
void main()
{
//clears the screen.
clrscr();
//declare variable type int
int a,b,c;
//The two numbers are declared which makes program non-flexible.
a=12;
b=10;
//calculates multiplication and save them in 'c'
c=a*b;
//show the output c
cout<<"multiplication of two numbers are  "<<c;
//get character
getch();
}
``````

output will be

multiplication of two numbers are 120.

Second program

``````#include<iostream.h>
#include<conio.h>
void main()
{
//clear the screen.
clrscr();
//declare variable type int
int a,b,c;
//Input the two numbers and save them in 'a' and 'b'
cout<<"Enter the first no."<<endl;
cin>>a;
cout<<"Enter the second no."<<endl;
cin>>b;
//calculate multiplication and save them in 'c'
c=a*b;
//show the output c
cout<<"multiplication of two numbers are "<<c;
//get character
getch();
}
``````

output will be

Enter the first no.
12
Enter the second no,
2
multiplication of two numbers are 24.

Third program

``````#include<iostream.h>
#include<conio.h>
void main()
{
//clear the screen.
clrscr();
//declare variable type int
int a,b,c,d;
//Input the three numbers and save them in 'a' and 'b' and 'c'.
cout<<"Enter the first no."<<endl;
cin>>a;
cout<<"Enter the second no."<<endl;
cin>>b;
cout<<"Enter the third no."<<endl;
cin>>c;
//calculate multiplication and save them in 'd'
d=a*b*c;
//show the output d
cout<<"multiplication of three numbers are "<<d;
//get character
getch();
}
``````

output will be

Enter the first no.
1
Enter the second no.
2
Enter the third no.
3

multiplication of three numbers are 6.

Fourth program

``````#include<iostream.h>
#include<conio.h>
void main()
{
//clear the screen.
clrscr();
//declare variable type int
int a,b,c,d,e;
//Input the four numbers and save them in 'a' , 'b','c' and'd'
cout<<"Enter the first no."<<endl;
cin>>a;
cout<<"Enter the second no."<<endl;
cin>>b;
cout<<"Enter the third no."<<endl;
cin>>c;
cout<<"Enter the fourth no."<<endl;
cin>>d;
//calculate multiplication and save them in 'e'
e=a*b*c*d;
//show the output e
cout<<"multiplication of four numbers are "<<e;
//get character
getch();
}
``````

output will be

Enter the first no.
2
Enter the second no.
3
Enter the third no.
2
Enter the fourth no.
10
multiplication of four numbers are 120.

How does it work.
1. you enter the numbers that are saved in their respective variables.
2. all are multiplied and saved in one variable.
3. multiplication is displayed on screen.

Extending it.
You can extend it by adding number of variables and their cout and cin and modifying multiplication variable.

Explanation.
1. Include ‘iostream.h’ and ‘conio.h’ files.