# If-Else Statements

Conditional statements, such as `if` and `else`, play a vital role in decision-making within C programs. They allow the execution of different blocks of code based on specified conditions. Let's delve into the syntax and usage of `if-else` statements.

## Basic Syntax of If-Else Statements

```c
#include <stdio.h>

int main() {
    int num = 10;

    // If-else statement
    if (num > 0) {
        printf("Positive number\n");
    } else {
        printf("Non-positive number\n");
    }

    return 0;
}
```

In this example, if `num` is greater than 0, the program prints "Positive number"; otherwise, it prints "Non-positive number."

## If-Else Statement Structure

```c
#include <stdio.h>

int main() {
    int num = 0;

    // If-else if-else structure
    if (num > 0) {
        printf("Positive number\n");
    } else if (num < 0) {
        printf("Negative number\n");
    } else {
        printf("Zero\n");
    }

    return 0;
}
```

Here, the program checks multiple conditions using `else if`. If `num` is positive, it prints "Positive number"; if negative, it prints "Negative number"; otherwise, it prints "Zero."

## Nested If-Else Statements

```c
#include <stdio.h>

int main() {
    int a = 5, b = 3;

    // Nested if-else statements
    if (a > 0) {
        if (b > 0) {
            printf("Both numbers are positive\n");
        } else {
            printf("Only 'a' is positive\n");
        }
    } else {
        printf("Both numbers are non-positive\n");
    }

    return 0;
}
```

Nested `if-else` statements allow for more complex decision-making structures. In this example, it checks if both `a` and `b` are positive, only `a` is positive, or both are non-positive.

## Practical Tips

* Use `if-else` statements for simple decision-making scenarios.
* Utilize `else if` to handle multiple conditions sequentially.
* Be cautious with nested `if-else` statements; they may impact code readability.

Understanding and effectively using `if-else` statements are essential skills for writing flexible and logic-driven C programs. If you have specific questions or if there are additional topics you'd like to explore, feel free to ask. Happy coding!
