Input Validation

Validation checks incoming values before the rest of the program trusts them.

input_validation.cpp

#include <iostream>

int main() {
    int requestedSeats = ;
    int fallbackSeats = 1;
    int maxSeats = 6;

    bool valid = requestedSeats >= 1 && requestedSeats <= maxSeats;
    int seats = valid ? requestedSeats : fallbackSeats;

    std::cout << "requestedSeats=" << requestedSeats << std::endl;
    std::cout << "valid=" << valid << std::endl;
    std::cout << "seats=" << seats << std::endl;
    return 0;
}

#include <iostream>

int main() {
    int requestedSeats = ;
    int fallbackSeats = 1;
    int maxSeats = 6;

    bool valid = requestedSeats >= 1 && requestedSeats <= maxSeats;
    int seats = valid ? requestedSeats : fallbackSeats;

    std::cout << "requestedSeats=" << requestedSeats << std::endl;
    std::cout << "valid=" << valid << std::endl;
    std::cout << "seats=" << seats << std::endl;
    return 0;
}

#include <iostream>

int main() {
    int requestedSeats = ;
    int fallbackSeats = 1;
    int maxSeats = 6;

    bool valid = requestedSeats >= 1 && requestedSeats <= maxSeats;
    int seats = valid ? requestedSeats : fallbackSeats;

    std::cout << "requestedSeats=" << requestedSeats << std::endl;
    std::cout << "valid=" << valid << std::endl;
    std::cout << "seats=" << seats << std::endl;
    return 0;
}

input validation Defensive code chooses a safe path when input falls outside the allowed range.