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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

#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

#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

#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!

Last modified: 25 February 2024