Choose Car By Applying Given Conditions C Programming Language

Making car selection decisions can often involve a complex evaluation of various factors such as budget, fuel efficiency, and seating capacity. In this article, you will learn how to apply conditional logic in C programming to automate and streamline the process of choosing a car based on predefined criteria.

Problem Statement

The challenge in selecting a car lies in matching personal preferences and constraints against a multitude of available options. Manually comparing every car against specific requirements can be time-consuming and prone to human error. A programmatic approach is needed to systematically filter and recommend cars based on user-defined conditions like maximum price, desired fuel economy, and passenger capacity, ensuring objective and consistent decision-making.

Example

Consider a scenario where a user is looking for a car that meets specific criteria. Input:

• Maximum Budget: $25,000
• Desired Fuel Efficiency (MPG): 30
• Minimum Seating Capacity: 5

Desired Output: Based on a hypothetical "Car Model X" with a price of $23,000, 32 MPG, and 5 seats, the program should output: "Car Model X meets your criteria!"

Background & Knowledge Prerequisites

To understand the solutions presented in this article, readers should have a basic understanding of:

• C Programming Fundamentals: Variables, data types, input/output operations (printf, scanf).
• Conditional Statements: if, else if, else.
• Logical Operators: && (AND), || (OR), ! (NOT).

No special libraries beyond the standard input/output library (stdio.h) are required.

Use Cases or Case Studies

Automating car selection logic can be beneficial in several real-world scenarios:

• Personal Car Buying Assistant: Helping individuals quickly narrow down car options based on their budget, family size, and environmental concerns.
• Dealership Inventory Management: Enabling salespeople to efficiently recommend suitable vehicles from their stock that match a customer's specific requirements.
• Fleet Management Systems: Assisting businesses in choosing appropriate vehicles for their fleet based on operational costs, cargo capacity, and passenger needs.
• Online Automotive Recommendation Engines: Powering backend logic for websites that suggest cars to users based on detailed preference inputs.
• Car Rental Services: Determining which class of vehicle to offer a customer based on their rental package and availability constraints.

Solution Approaches

Here are a few approaches to implementing car selection logic in C, ranging from simple to more structured methods.

Approach 1: Simple if-else Statements

This approach uses a straightforward sequence of if-else if-else statements to check conditions sequentially.

Summary: Checks each condition independently, making decisions based on the first met criterion.

// Simple Car Selector
#include <stdio.h>

int main() {
    // Step 1: Declare variables for car criteria
    int price, fuel_efficiency, seating_capacity;

    // Step 2: Get car details from user
    printf("Enter car price: $");
    scanf("%d", &price);
    printf("Enter car fuel efficiency (MPG): ");
    scanf("%d", &fuel_efficiency);
    printf("Enter car seating capacity: ");
    scanf("%d", &seating_capacity);

    // Step 3: Apply conditions using if-else statements
    printf("\\nEvaluating car...\\n");
    if (price <= 20000 && fuel_efficiency >= 35 && seating_capacity >= 4) {
        printf("This car is an EXCELLENT match for a budget-friendly, efficient, family car!\\n");
    } else if (price <= 30000 && fuel_efficiency >= 25 && seating_capacity >= 5) {
        printf("This car is a GOOD match for a standard family car.\\n");
    } else if (price <= 40000 && fuel_efficiency >= 20) {
        printf("This car is a DECENT option, perhaps a larger or luxury model.\\n");
    } else {
        printf("This car does not fit typical criteria for general use.\\n");
    }

    return 0;
}

Run

Sample Output:

Enter car price: $23000
Enter car fuel efficiency (MPG): 32
Enter car seating capacity: 5

Evaluating car...
This car is a GOOD match for a standard family car.

Stepwise Explanation:

1. Declare Variables: price, fuel_efficiency, and seating_capacity are declared to store integer values.
2. Get Input: The program prompts the user to enter the car's attributes using printf and reads the input using scanf.
3. Apply Conditions: A series of if-else if-else statements checks if the entered car details match predefined criteria.

• The first if checks for strict criteria (budget-friendly, very efficient, decent seating).
• The else if checks for slightly relaxed criteria (standard family car).
• Another else if checks for broader criteria (larger/luxury model).
• The final else catches any car that doesn't fit the above categories.

1. Print Result: A message indicating whether the car fits the criteria is printed to the console.

Approach 2: Using Logical Operators for Combined Conditions

This approach refines the conditional checks by combining multiple criteria into single, more complex expressions using logical AND (&&) and OR (||) operators. This leads to more precise recommendations.

Summary: Combines conditions using && and || to create robust and specific criteria evaluations.

// Advanced Car Selector with Logical Operators
#include <stdio.h>

int main() {
    // Step 1: Declare variables for car criteria
    int price, fuel_efficiency, seating_capacity;
    char car_type[20]; // e.g., "Sedan", "SUV", "Hatchback"

    // Step 2: Get car details from user
    printf("Enter car price: $");
    scanf("%d", &price);
    printf("Enter car fuel efficiency (MPG): ");
    scanf("%d", &fuel_efficiency);
    printf("Enter car seating capacity: ");
    scanf("%d", &seating_capacity);
    printf("Enter car type (e.g., Sedan, SUV, Hatchback): ");
    scanf("%19s", car_type); // Read string, limit to 19 chars + null terminator

    // Step 3: Apply conditions using logical operators
    printf("\\nEvaluating car...\\n");

    // Condition for a family SUV
    if (price <= 40000 && fuel_efficiency >= 20 && seating_capacity >= 5 &&
        (strcmp(car_type, "SUV") == 0 || strcmp(car_type, "Minivan") == 0)) {
        printf("This car is suitable for a family SUV/Minivan!\\n");
    }
    // Condition for an efficient city car
    else if (price <= 25000 && fuel_efficiency >= 35 && seating_capacity <= 5 &&
             (strcmp(car_type, "Sedan") == 0 || strcmp(car_type, "Hatchback") == 0)) {
        printf("This car is ideal for city driving and efficiency!\\n");
    }
    // Condition for a high-performance/luxury car (less focus on efficiency, more on price/type)
    else if (price > 40000 && fuel_efficiency >= 15 && seating_capacity >= 2 &&
             (strcmp(car_type, "Sports") == 0 || strcmp(car_type, "Luxury") == 0)) {
        printf("This car is a high-performance or luxury option.\\n");
    }
    else {
        printf("This car does not fit any specific categorized criteria.\\n");
    }

    return 0;
}

Run

Sample Output:

Enter car price: $35000
Enter car fuel efficiency (MPG): 25
Enter car seating capacity: 6
Enter car type (e.g., Sedan, SUV, Hatchback): SUV

Evaluating car...
This car is suitable for a family SUV/Minivan!

Stepwise Explanation:

1. Declare Variables: Adds a car_type character array to handle string input for car categories.
2. Get Input: Includes a prompt for the car type. Note the use of scanf("%19s", car_type) to safely read string input and prevent buffer overflows.
3. Apply Conditions with Logical Operators:

• The if statements now combine multiple conditions using && (AND) to ensure all specified criteria for a particular category (e.g., family SUV) are met.
• strcmp(car_type, "SUV") == 0 is used to compare the entered car type string with "SUV". strcmp returns 0 if the strings are identical.
• || (OR) is used within parentheses to allow for multiple car types to satisfy a category (e.g., "SUV" *or* "Minivan").

1. Print Result: Outputs a more specific recommendation based on the combined criteria.

Approach 3: Using a switch Statement for Categorical Choices

When a primary selection criterion is categorical (like car type), a switch statement can make the code cleaner and more readable than multiple if-else if blocks for that specific criterion.

Summary: Uses a switch statement for the main car category, then nested if-else for other attributes.

// Car Selector with Switch and Nested Conditions
#include <stdio.h>
#include <string.h> // Required for strcmp

int main() {
    // Step 1: Declare variables for car criteria
    int price, fuel_efficiency, seating_capacity;
    char car_type[20];

    // Step 2: Get car details from user
    printf("Enter car type (Sedan, SUV, Hatchback, Sports): ");
    scanf("%19s", car_type);
    printf("Enter car price: $");
    scanf("%d", &price);
    printf("Enter car fuel efficiency (MPG): ");
    scanf("%d", &fuel_efficiency);
    printf("Enter car seating capacity: ");
    scanf("%d", &seating_capacity);

    // Step 3: Apply conditions using a switch statement for car type
    printf("\\nEvaluating car...\\n");

    // Convert car_type to an integer for switch (simple hash or enum for more types)
    // For simplicity, we'll manually check and set a "type_code"
    // In a real application, you might use enums or more robust string handling
    int type_code = 0; // 1: Sedan, 2: SUV, 3: Hatchback, 4: Sports

    if (strcmp(car_type, "Sedan") == 0) type_code = 1;
    else if (strcmp(car_type, "SUV") == 0) type_code = 2;
    else if (strcmp(car_type, "Hatchback") == 0) type_code = 3;
    else if (strcmp(car_type, "Sports") == 0) type_code = 4;
    else type_code = 0; // Unknown type

    switch (type_code) {
        case 1: // Sedan
            if (price <= 30000 && fuel_efficiency >= 30 && seating_capacity >= 4) {
                printf("This Sedan is a great choice for balanced performance and family use.\\n");
            } else {
                printf("This Sedan doesn't quite meet typical criteria for its type.\\n");
            }
            break;
        case 2: // SUV
            if (price <= 50000 && fuel_efficiency >= 20 && seating_capacity >= 5) {
                printf("This SUV is suitable for families and versatility.\\n");
            } else {
                printf("This SUV doesn't quite meet typical criteria for its type.\\n");
            }
            break;
        case 3: // Hatchback
            if (price <= 25000 && fuel_efficiency >= 35 && seating_capacity >= 4) {
                printf("This Hatchback is excellent for city driving and fuel economy.\\n");
            } else {
                printf("This Hatchback doesn't quite meet typical criteria for its type.\\n");
            }
            break;
        case 4: // Sports Car
            if (price >= 40000 && fuel_efficiency >= 15 && seating_capacity >= 2) {
                printf("This Sports Car is a high-performance, enthusiast's choice.\\n");
            } else {
                printf("This Sports Car doesn't quite meet typical criteria for its type.\\n");
            }
            break;
        default:
            printf("Car type not recognized or no specific recommendations available.\\n");
            break;
    }

    return 0;
}

Run

Sample Output:

Enter car type (Sedan, SUV, Hatchback, Sports): Hatchback
Enter car price: $22000
Enter car fuel efficiency (MPG): 38
Enter car seating capacity: 4

Evaluating car...
This Hatchback is excellent for city driving and fuel economy.

Stepwise Explanation:

1. Declare Variables & Include string.h: Similar variables, but string.h is explicitly included for strcmp.
2. Get Input: Prompts for car type first, followed by other attributes.
3. Prepare for switch: Since switch works only with integer or character types, the car_type string is converted into a numeric type_code using a series of if-else if statements. In more complex scenarios, an enum could be used.
4. Apply switch Statement: The program then enters a switch block based on type_code.

• Each case corresponds to a specific car type.
• Inside each case, nested if-else statements apply further conditions (price, efficiency, seating) relevant to that particular car type. This allows for tailored criteria per category.
• A default case handles unrecognized car types.

1. Print Result: A tailored message is displayed based on the car type and whether it meets its specific sub-criteria.

Conclusion

Implementing car selection logic in C involves applying conditional statements to match car attributes against desired criteria. Whether using sequential if-else statements for basic filtering, combining conditions with logical operators for more granular control, or structuring decisions with switch statements for categorical choices, C provides the tools to build robust decision-making programs. Each approach offers different levels of specificity and readability, allowing developers to choose the best fit for their application's complexity.

Summary

• Problem: Manually choosing a car from many options is inefficient; C programming provides systematic decision logic.
• Approach 1 (if-else): Simple, sequential checks for basic criteria.
• Approach 2 (Logical Operators): Combines multiple conditions (&&, ||) for precise, complex filtering.
• Approach 3 (switch): Uses a switch statement for primary categorical choices (e.g., car type), with nested if-else for specific attributes within each category, improving code organization.
• Key Takeaway: C's conditional statements are powerful for creating automated car recommendation systems based on various user preferences.