There are only 4.29 billion possible values of an int32, so even if you used 2 lines for each case, it’d still be under 10 billion lines of code

bool isOdd(int num) {
    if (num == 1)
        { return true; }
    if (num == 2)
        { return false; }
    if (num == 3)
        { return true; }
    …
}