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 the following C programming topics:
- C Programming Operators
- C if...else Statement
This program takes a number from the user and checks whether that number is either positive or negative or zero.
Check Positive or Negative Using Nested if...else
#include <stdio.h>
int main() {
double num;
printf("Enter a number: ");
scanf("%lf", &num);
if (num <= 0.0) {
if (num == 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.
Check Positive or Negative Using if...else Ladder
#include <stdio.h>
int main() {
double num;
printf("Enter a number: ");
scanf("%lf", &num);
if (num < 0.0)
printf("You entered a negative number.");
else if (num > 0.0)
printf("You entered a positive number.");
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.