IF...ELSE Statement

Definition:

  • IF...ELSE Statement also used to control the flow of program based on condition because it is the part of IF Statement.
  • IF...ELSE Statement's body will execute only when IF Statement condition evaluated as false.
  • IF Statement followed by optional ELSE Statement which execute only when IF Statement condition is false.

Syntax:

The syntax of IF...ELSE Statement in C-Language

           if(Test Condition)
                 {
                    //Statement(s) will execute if the Test Condition is true
                  }
            else
                 {
                   //Statement(s) will execute if the Test Condition is false
                  }

How IF...ELSE Statement Works:

 If the Test Condition is checked as true:

  • Statement(s) inside the body of IF Loop will execute
  • Statement(s) inside the body of ELSE will skipped from execution

If the Test Condition is checked as false:

  • Statement(s) inside the body of IF Loop will not executed means skipped   
  • Statement(s) inside the body of ELSE will execute

Illustration of IF...ELSE Statement:

CASE-1: Test Condition is True

        int a = 4;
        if(a<8)
           {
             //Statement(s) inside the body of IF Loop will execute 
            }
        else
           {
             //Statement(s) inside the body of ELSE will skipped from execution
            }

CASE-2: Test Condition is False

       int a = 4;
       if(a>8)
          {
            //Statement(s) inside the body of IF Loop will not executed means skipped 
           }
       else
          {
            //Statement(s) inside the body of ELSE will execute
           }

Program: Write a C program to demonstrate the IF...ELSE Statement

#include<stdio.h>
int main()
{
 int number;
 printf("Enter the value of number:");
 scanf("%d", &number);
      if(number>0)
             {
               printf("The entered number is positive.");
             }
       else
           {
             printf("The entered number is negative.");
           }
   }

Output:

Enter the value of number: 3
The entered number is positive.

Enter the value of number: -3
The entered number is negative.