C if else statement

The if-else statement is a fundamental part of decision-making in C programming. It allows your code to make choices based on certain conditions, making your programs dynamic and flexible.

What is the if-else Statement?

In simple terms, the if-else statement lets you execute one block of code if a condition is true and another block if the condition is false.

Syntax

if (condition) {
    // Code to execute if the condition is true
} else {
    // Code to execute if the condition is false
}

How It Works

1. The condition inside the parentheses is evaluated.
2. If the condition is true (non-zero), the code inside the if block runs.
3. If the condition is false (zero), the code inside the else block runs.

Example

#include <stdio.h>

int main() {
    int number = 10;

    if (number > 5) {
        printf("The number is greater than 5.\n");
    } else {
        printf("The number is 5 or less.\n");
    }

    return 0;
}

Output:
The number is greater than 5.

Key Points to Remember

1. Conditions: Any valid C expression that evaluates to true (non-zero) or false (zero) can be used.
2. Else is Optional: You can use if without else if no alternative action is needed.
   Example:

   if (number > 0) {
       printf("Positive number.\n");
   }
   

3. Nesting: You can nest multiple if-else statements for complex conditions.
   Example:

   if (number > 0) {
       printf("Positive number.\n");
   } else if (number < 0) {
       printf("Negative number.\n");
   } else {
       printf("Zero.\n");
   }
   

The if-else statement is a cornerstone of programming logic. It allows your programs to respond dynamically to different scenarios, making them more robust and interactive.