WAP to input any number and check whether a Number is Positive or Negtive

C Program to Check Whether a Number is Positive or Negative

In this example, you will learn to check whether a number (entered by the user) is negative or positive.

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

• C Programming Operators
• C if, if...else and Nested if...else Statement

This program takes a number from the user and checks whether that number is either positive or negative or zero.

Example #1: Check if a Number is Positive or Negative Using if...else

#include <stdio.h>

int main()

{

    double number;

    printf("Enter a number: ");

    scanf("%lf", &number);

    if (number <= 0.0)

    {

        if (number == 0.0)

            printf("You entered 0.");

        else

            printf("You entered a negative number.");

    }

    else

        printf("You entered a positive number.");

    return 0;

}

You can also solve this problem using nested if else statement.

Example #2: Check if a Number is Positive or Negative Using Nested if...else

#include <stdio.h>

int main()

{

    double number;

    printf("Enter a number: ");

    scanf("%lf", &number);

    // true if number is less than 0

    if (number < 0.0)

        printf("You entered a negative number.");

    // true if number is greater than 0

    else if ( number > 0.0)

        printf("You entered a positive number.");

    // if both test expression is evaluated to false

    else

        printf("You entered 0.");

    return 0;

}

Output 1

Enter a number: 12.3

You entered a positive number.

Output 2

Enter a number: 0

You entered 0.