Swap Two Numbers in C

By -
  Swap Two Numbers in C In this example, you will learn to swap two numbers in C programming using two different techniques. To understand this example, you should have the knowledge of the following C programming topics: C Data Types C Programming Operators C Input Output (I/O) Swap Numbers Using Temporary Variable # include <stdio.h> int main () { double first, second, temp; printf ( "Enter first number: " ); scanf ( "%lf" , &first); printf ( "Enter second number: " ); scanf ( "%lf" , &second); // Value of first is assigned to temp temp = first; // Value of second is assigned to first first = second; // Value of temp (initial value of first) is assigned to second second = temp; printf ( "\nAfter swapping, firstNumber = %.2lf\n" , first); printf ( "After swapping, secondNumber = %.2lf" , second); return 0 ; } Output ...
Post a Comment

Check Whether a Number is Prime or Not in C

By -

 

Check Whether a Number is Prime or Not in C

In this example, you will learn to check whether an integer entered by the user is a prime number or not.

To understand this example, you should have the knowledge of the following C programming topics:

  • C if...else Statement
  • C for Loop
  • C break and continue

A prime number is a positive integer that is divisible only by 1 and itself. For example: 2, 3, 5, 7, 11, 13, 17

Program to Check Prime Number

#include <stdio.h>
int main() {
    int n, i, flag = 0;
    printf("Enter a positive integer: ");
    scanf("%d", &n);

    for (i = 2; i <= n / 2; ++i) {

        // condition for non-prime
        if (n % i == 0) {
            flag = 1;
            break;
        }
    }

    if (n == 1) {
        printf("1 is neither prime nor composite.");
    }
    else {
        if (flag == 0)
            printf("%d is a prime number.", n);
        else
            printf("%d is not a prime number.", n);
    }

    return 0;
}

Output

Enter a positive integer: 29
29 is a prime number.
In the program, a for loop is iterated from i = 2 to i < n/2.
In each iteration, whether n is perfectly divisible by i is checked using:
if (n % i == 0) {
   
}

If n is perfectly divisible by i, n is not a prime number. In this case, flag is set to 1, and the loop is terminated using the break statement.
After the loop, if n is a prime number, flag will still be 0. However, if n is a non-prime number, flag will be 1.
Visit this page to learn how you can print all the prime numbers between two intervals.

Comments

Post a Comment

Popular posts from this blog

C Program to Print an Integer (Entered by the User)

By -
Image
  C Program to Print an Integer (Entered by the User) In this example, the integer entered by the user is stored in a variable and printed on the screen. To understand this example, you should have the knowledge of the following C programming topics: C Variables, Constants and Literals C Data Types C Input Output (I/O) Program to Print an Integer # include <stdio.h> int main () { int number; printf ( "Enter an integer: " ); // reads and stores input scanf ( "%d" , &number); // displays output printf ( "You entered: %d" , number); return 0 ; } Terminal Code : Output Enter an integer: 25 You entered: 25 Terminal Output : In this program, an integer variable  number  is declared. int number; Then, the user is asked to enter an integer number. This number is stored in the  number  variable. printf ( "Enter an integer: " ); scanf ( "%d" , &number); Finally, the value stor...
Read more

Simple Calculator Using switch case in C

By -
  Simple Calculator program Using switch case in C In this example, you will learn to create a simple calculator in C programming using the switch statement. To understand this example, you should have the knowledge of the following C programming topics: C switch Statement C break and continue This program takes an arithmetic operator  +, -, *, /  and two operands from the user. Then, it performs the calculation on the two operands depending upon the operator entered by the user. Simple Calculator using switch Statement # include <stdio.h> int main () { char operator ; double first, second; printf ( "Enter an operator (+, -, *,): " ); scanf ( "%c" , & operator ); printf ( "Enter two operands: " ); scanf ( "%lf %lf" , &first, &second); switch ( operator ) { case '+' : printf ( "%.1lf + %.1lf = %.1lf" , first, second, first + second); break ; case ...
Read more

Add Two Integers in C language

By -
Image
  Add Two Integers in C language In this example, the user is asked to enter two integers. Then, the sum of these two integers is calculated and displayed on the screen. To understand this example, you should have the knowledge of the following C programming topics: C Data Types C Variables, Constants and Literals C Input Output (I/O) C Programming Operators Program to Add Two Integers # include <stdio.h> int main () { int number1, number2, sum; printf ( "Enter two integers: " ); scanf ( "%d %d" , &number1, &number2); // calculating sum sum = number1 + number2; printf ( "%d + %d = %d" , number1, number2, sum); return 0 ; } Terminal Code : Output : Enter two integers: 12 11 12 + 11 = 23 Terminal Output : In this program, the user is asked to enter two integers. These two integers are stored in variables  number1  and  number2  respectively. printf ( "Enter two integers: " ); sc...
Read more