Nested If - Else

Part of the Fundamentals section of Coddy's C journey — lesson 31 of 63.

We can nest if-else statements within each other. This allows us to create hierarchical decision-making structures.

For example:

if (age > 18) {
    if (hasLicense) {
        printf("You can drive");
    } else {
        printf("Get a license first");
    }
} else {
    printf("Too young to drive");
}

It can be infinitely nested:

if (condition1) {
    if (condition2) {
        if (condition3) {
            // if condition1, condition2 and condition3 are true
        }
    }
}

Challenge

Easy

Create a program that checks if someone can ride a rollercoaster. The requirements are:

Must be at least 12 years old
Must be taller than 150cm
If they meet both requirements but are under 15, they need adult supervision

Print exactly these messages for each case:

If too young: Sorry, you are too young
If not tall enough: Sorry, you are not tall enough
If under 15 and no adult: Sorry, you need an adult with you
If under 15 with adult: You can ride with adult supervision!
If 15 or older and tall enough: You can ride by yourself!

Cheat sheet

You can nest if-else statements within each other to create hierarchical decision-making structures:

if (age > 18) {
    if (hasLicense) {
        printf("You can drive");
    } else {
        printf("Get a license first");
    }
} else {
    printf("Too young to drive");
}

Nesting can be done infinitely:

if (condition1) {
    if (condition2) {
        if (condition3) {
            // if condition1, condition2 and condition3 are true
        }
    }
}

Try it yourself

#include <stdio.h>

int main() {
    int age, height;
    int hasAdult;
    scanf("%d %d %d", &age, &height, &hasAdult); // Don't change this line

    // Write your code below
    
    return 0;
}

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Fundamentals

1Introduction

C Language Hello World!Comments Basic Program Structure

4Control Flow

If Statement If - Else Else-If Switch Case Ternary Conditional Operator Recap ChallengeNested If - Else

7Functions

Declare a Function Return Types Parameters Recap Challenge #1 Recursion Basics Function Prototypes Recap Challenge #2