1. TO DESIGN A CALCULATOR USING C LANGUAGE
BY- SAURABH KHETAN
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0 = % /

2.  Hello friends, my name is Saurabh Khetan.
 This time i am here with a presentation showing you to
design your own calculator using a console application.
 The calculator over here is designed using a basic
programming language i.e C language.
 Programming of the calculator is tested on the Microsoft
visual C++ express.
 It is a software use to code the C programs.
 As I have mentioned in my earlier presentation of prime
numbers, the same program can be coded, compiled and
executed in turbo C++ as well.

3.  Our calculator is a simple calculator capable of
performing operations on two numbers.
 The numbers might be decimal or non-decimal.
 User is allowed to enter the desired numbers and the
result will be displayed on the screen.
 The calculator will perform four basic operations of
addition, subtraction, multiplication and division.
 The students interested in software engineering and want
to learn basic programming and build their logic may
find this program interesting.
 The program is constructed using switching method in C
language.

4.  The switching method in C language provides an option
to the user which operation he desires to perform.
 Thus, a program wherein there are too many options
listed, the user can select a particular option and obtain
the result of that operation.
 The switch case in C programming can be done using a
very simple set of syntaxes.
 Now we move to our first switch case program in C
language.
 It will clarify our doubts about the design of our C
program.

5. #include<stdio.h>
int main()
{
/*This is a calculator programme. Calculator is able to perform the operation of two numbers*/
int num;float a,b,c;
printf("Hello friends this is a calculator ");
printf("nchoose a number from the menu to operate the desired function");
printf("npress 1 for additionnpress 2 for subtractionnpress 3 for multiplicationnpress 4 for division");
scanf("%d",&num);
/*The operation is performed using the switch case method*/
switch(num)
{
case 1:
printf("enter two numbers");
scanf("%f%f",&a,&b);
c= a+b;
printf("the addition of two numbers is %f",c);
break;
case 2:
printf("enter two numbers");
scanf("%f%f",&a,&b);
c=a-b;
printf("the subtraction of two numbers is %f",c);
break;
case 3:
printf("enter two numbers");
scanf("%f%f",&a,&b);
c=a*b;
printf("the multiplication of two numbers is %f",c);
break;
case 4:
printf("enter two numbers");
scanf("%f%f",&a,&b);
c=a/b;
printf("the division of two numbers is %f",c);
}
}

6.  The previous slide is the exact program to design our
own calculator.
 The program had been written in a single slide to avoid
the confusion of the readers.
 The program as I said had been tested and works
efficiently.
 The text entered within /**/ are the comments in the
program to clarify the usage and construction.
 All you need to know about this program is the basic use
of the header files, basic functions and the syntax.
 You can just copy this program from the slide or instead
write it in the editor of the software of your choice.

7.  To learn about the C language and more of it, you may go
for the book named: Let us C by Mr. Yashavant Kanetkar.
 Or the more efficient course offered by him with the help
of Dvds namely Quest course would be much better.
 After you written the program in the editor, build it and
run it.
 The moment you run it you will experience the fun while
programming.
 This program might develop your interest in the software
area.

8.  So friends just enjoy this program and do feed me
with your comments after seeing this presentation.
 And do wait for my next upload.
 For any other queries u can mail me on this address
saurabh.khetan53@gmail.com
 Any problem regarding this program and any kind of
query would be resolved.