This hadnout explains ‘switch-case’ statement in C.

1. C-Programming
Walchand Institute of Technology (RC1131), Solapur Page 1
Handout#6
Assignment/Program Statement:
Write a C program using ‘switch-case’ statement - to read two values from user
and perform addition, subtraction, multiplication, division and modulus division
Learning Objectives:
Students will be able to
- write the syntax of switch-case statement
- draw the flowchart for switch-case menu driven solution
- write the algorithm for switch-case menu driven
- write the program using switch-case statement
Theory:
 A switch statement allows a variable to be tested for equality against a list
of values. Each value is called a case, and the variable being switched on is
checked for each switch case.
 The syntax for a switch statement in C programming language is as follows-
switch (n)
{
case constant1:
// code to be executed if n is equal to constant1;
break;
case constant2:
// code to be executed if n is equal to constant2;
break;
.
.
.
default:
// code to be executed if n doesn't match any constant
}
 When a case constant is found that matches the switch expression, control of
the program passes to the block of code associated with that case.

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Walchand Institute of Technology (RC1131), Solapur Page 2
 In the above pseudo code, suppose the value of n is equal to constant2. The
compiler will execute the block of code associate with the case statement
until the end of switch block, or until the break statement is encountered.
 The break statement is used to prevent the code running into the next case.
Example: C code to perform addition, subtraction, multiplication and division
switch(operator)
{
case '+':
printf("%.1lf + %.1lf = %.1lf",firstNumber, secondNumber,
firstNumber+secondNumber);
break;
case '-':
printf("%.1lf - %.1lf = %.1lf",firstNumber, secondNumber,
firstNumber-secondNumber);
break;
case '*':
printf("%.1lf * %.1lf = %.1lf",firstNumber, secondNumber,
firstNumber*secondNumber);
break;
case '/':
printf("%.1lf / %.1lf = %.1lf",firstNumber, secondNumber,
firstNumber/firstNumber);
break;
default:
printf("Error! operator is not correct");
}
[Reference: http://www.programiz.com/c-programming/c-switch-case-statement ]
Flow diagram for switch case:

3. C-Programming
Walchand Institute of Technology (RC1131), Solapur Page 3

4. C-Programming
Walchand Institute of Technology (RC1131), Solapur Page 4
Flowchart for Problem Statement:

5. C-Programming
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Algorithm:
1. Start
2. Read operand 1 and operand 2
3. Read choice
4. If choice = 1
answer = operand 1 + operand 2
display the answer
go to 5
else
answer = operand 1 - operand 2
display the answer
go to 5
else
answer = operand 1 * operand 2
display the answer
go to 5
else
answer = operand 1 / operand 2
display the answer
go to 5
else
answer = operand 1 % operand 2
display the answer
go to 5
else
display the answer
go to 5
5. Stop

6. C-Programming
Walchand Institute of Technology (RC1131), Solapur Page 6
Program:
#include<stdio.h>
void main()
{
int op1, op2, ans, choice;
clrscr();
/*Code to read input operand1 and operand2*/
printf("n Enter First Number:");
scanf("%d", &op1);
printf("n Enter Second Number:");
scanf("%d", &op2);
printf("nn Menu");
printf("n 1. Addition");
printf("n 2. Subtraction");
printf("n 3. Multiplication");
printf("n 4. Division");
printf("n 5. Modulus Division");
printf("n 6. Exit");
printf("n Enter your choice:");
scanf("%d",&choice);
switch(choice)
{
case 1: ans = op1+op2;
printf("n Addition = %d",ans);
break;
case 2: ans = op1-op2;
printf("n Subtraction = %d",ans);
break;
case 3: ans = op1*op2;
printf("n Multiplication = %d", ans);
break;
case 4: ans = op1/op2;
printf("n Division = %d",ans);

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Walchand Institute of Technology (RC1131), Solapur Page 7
break;
case 5: ans = op1%op2;
printf("n Modulus operator = %d",ans);
break;
` default: printf("n Wrong choice...");
}
getch();
}
Input:
Enter First Number: 12
Enter Second Number: 12
Menu
1. Addition
2. Subtraction
3. Multiplication
4. Division
5. Modulus Division
6. Exit
Enter your choice:1
Output:
Addition = 12
Practice Problem Statement:
1. Write a program to take an integer from user and perform following operations
a) Check whether number is even or odd
b) Check whether number is prime or not
c) Calculate its factorial
d) Check whether number is positive or negative

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Conclusion:
Thus a C program using ‘switch-case’ statement - to read two values from user and
perform addition, subtraction, multiplication, division and modulus division is
implemented.
Learning Outcomes:
At the end of this assignment, students are able to
- write the syntax of switch-case statement
- draw the flowchart for switch-case menu driven solution
- write the algorithm for switch-case menu driven
- write the program using switch-case statement