Objectives:

The main objective of this lab experiment to guide you through a series of C programming

problems, using the control/branching statements i.e. if, if-else, conditional operator.

Exercise 1: Write a C program to check whether two numbers entered by the user are

equal or not.

Exercise 2: Write a C program to check whether an integer number entered by the user is

even or odd.

Exercise 3: Write a C program to check whether a year entered by the user is leap year of

not.

Definition of leap year:

Rule 1: A year is called leap year if it is divisible by 400.

For example: 1600, 2000 etc leap year while 1500, 1700 are not leap year.

Rule 2: If year is not divisible by 400 as well as 100 but it is divisible by 4 then that year is also

leap year.

For example: 2004, 2008, 1012 are leap year.

Lab Assignment: Write a C program that reads in two numbers from the user along with

an operator to perform addition, subtraction, multiplication or division. It calculates the

results depending on the operator and displays the result. If the user enters any invalid

operators, the program notifies the user.

A sample output is given below:

Fall 2014 Semester

ETE 105 LAB [Section:1]

Experiment 3: C Programs using branching Statements

Name: ID:

Enter two numbers and an operator in the format: number1 operator number2

Note that valid operators are:

addition --> +

subtraction --> -

multiplication --> *

division --> /

15.1+6.2

The result is 21.299999

Solutions

Exercise 1:

#include <stdio.h>

int main()

{

int num1, num2;

printf("Enter two numbers\n");

scanf("%d %d",&num1, &num2);

if(num1==num2)

printf("%d and %d are equal", num1, num2);

else

printf("%d and %d are not equal", num1, num2);

return 0;

}

Exercise 2:

#include <stdio.h>

int main()

{

int num;

printf("Enter an integer you want to check.\n");

scanf("%d",&num);

if((num%2)==0)

printf("%d is even",num);

else

printf("%d is odd",num);

return 0;

}

Exercise 3:

Code 1:

#include<stdio.h>

int main()

{

int year;

printf("Enter any year: ");

scanf("%d",&year);

if((year%400==0)||((year%4==0)&&(year%100!=0)))

printf("%d is a leap year",year);

else

printf("%d is not a leap year",year);

return 0;

}

Code 2:

#include <stdio.h>

int main()

{

int year;

printf("Enter any year: ");

scanf("%d",&year);

if(year%400==0)

printf("%d is a leap year", year);

else

if((year%100!=0)&&(year%4==0))

printf("%d is a leap year", year);

else

printf("%d is not a leap year", year);

return 0;

}

Lab Assignment:

#include <stdio.h>

main()

{

char o;

float num1, num2, result;

printf("Enter two numbers and an operator in the format: number1

operator number2\n\n");

printf("Note that valid operators are\n");

printf("addition --> +\n");

printf("subtraction --> -\n");

printf("multiplication --> *\n");

printf("division --> /\n\n");

scanf("%f %c %f", &num1, &o, &num2);

if(o=='+')

result = num1+num2;

else if(o=='-')

result = num1-num2;

else if(o=='*')

result = num1*num2;

else if(o=='/')

result = num1/num2;

else

printf("Invalid operator!\n");

printf("The result is %f\n", result);

}