/*test1：斐波那契数列（控制流 + 函数调用）*/
int fib(int n) {
    if (n < 1){
        return n;
    } else {
    return fib(n - 1) + fib(n - 2);
    }
}

int main() {
    int y;
    int x;
    x = 5 * 2 + 2;
    a = 2 == 2;
    x = fib(6);
    return x;
}