C if-else Statements

C "If else statements" also control the program flow based on conditions such as "if statements"; the only difference is that it executes some statement code block if the expression is true; otherwise, it executes the else statement code block.

The basic format of if else Statement is:

Syntax:

if(test_expression)
{
    //execute your code
}
else
{
    //execute your code
}

Figure - Flowchart of if-else Statement:

c-if-else

Example of a C Program to Demonstrate if-else Statement

Example:

#include<stdio.h>

void main()
{
    int a, b;

    printf("Please enter the value for a:");
    scanf("%d", &a);

    printf("\nPlease the value for b:");
    scanf("%d", &b);

    if (a > b) {  
        printf("\n a is greater");
    } else {  
        printf("\n b is greater");
    }
}

Program Output:

c-if-else statement 1

Example:

#include<stdio.h>

void main() {
    int num;
    printf("Enter the number:");
    scanf("%d", &num);

    /* check whether the number is negative number */
    if (num < 0)
        printf("The number is negative.");
    else
        printf("The number is positive."); 
}

Program Output:

c-if-else-statement 2

if-else Statements in C - Video Tutorial

Please watch this video tutorial to understand "C if-else Statements" in more depth.