关于构造函数，洛谷的编译器

struct myint {
    long long carry;
    long long num;
    myint(long long a = 0, long long b = 0)
    {
        carry = a;
        num = b;
    }
    bool operator < (const myint &a)
    {
        if (carry < a.carry)
            return true;
        else if (carry > a.carry)
            return false;
        else
            return num < a.num;
    }
    myint operator * (const int &a)
    {
        long long t;
        myint ret;
        t = num*a;
        ret.num = t%mod;
        ret.carry = carry + t / mod;
        return ret;
    }
    bool operator != (myint &a)
    {
        if (carry != a.carry || num != a.num)
            return true;
        return false;
    }
};
const myint zero;
const myint one = { 0,1 };
const myint MAX_myint = { INF,INF };