CP-code-snippets/Mint.cpp at main · satyarth413/CP-code-snippets · GitHub

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const int MOD = 1000000007;
// const int MOD = 998244353;
struct Mint {
    int val;

    Mint(long long v = 0) {
        if (v < 0)
            v = v % MOD + MOD;
        if (v >= MOD)
            v %= MOD;
        val = v;
    }

    static int mod_inv(int a, int m = MOD) {
        int g = m, r = a, x = 0, y = 1;
        while (r != 0) {
            int q = g / r;
            g %= r; swap(g, r);
            x -= q * y; swap(x, y);
        }
        return x < 0 ? x + m : x;
    }
    explicit operator int() const {
        return val;
    }
    Mint& operator+=(const Mint &other) {
        val += other.val;
        if (val >= MOD) val -= MOD;
        return *this;
    }
    Mint& operator-=(const Mint &other) {
        val -= other.val;
        if (val < 0) val += MOD;
        return *this;
    }
    static unsigned fast_mod(uint64_t x, unsigned m = MOD) {
#if !defined(_WIN32) || defined(_WIN64)
        return x % m;
#endif
        unsigned x_high = x >> 32, x_low = (unsigned) x;
        unsigned quot, rem;
        asm("divl %4\n"
            : "=a" (quot), "=d" (rem)
            : "d" (x_high), "a" (x_low), "r" (m));
        return rem;
    }
    Mint& operator*=(const Mint &other) {
        val = fast_mod((uint64_t) val * other.val);
        return *this;
    }
    Mint& operator/=(const Mint &other) {
        return *this *= other.inv();
    }
    friend Mint operator+(const Mint &a, const Mint &b) { return Mint(a) += b; }
    friend Mint operator-(const Mint &a, const Mint &b) { return Mint(a) -= b; }
    friend Mint operator*(const Mint &a, const Mint &b) { return Mint(a) *= b; }
    friend Mint operator/(const Mint &a, const Mint &b) { return Mint(a) /= b; }
    Mint& operator++() {
        val = val == MOD - 1 ? 0 : val + 1;
        return *this;
    }
    Mint& operator--() {
        val = val == 0 ? MOD - 1 : val - 1;
        return *this;
    }
    Mint operator++(int32_t) { Mint before = *this; ++*this; return before; }
    Mint operator--(int32_t) { Mint before = *this; --*this; return before; }
    Mint operator-() const {
        return val == 0 ? 0 : MOD - val;
    }
    bool operator==(const Mint &other) const { return val == other.val; }
    bool operator!=(const Mint &other) const { return val != other.val; }
    Mint inv() const {
        return mod_inv(val);
    }
    Mint power(long long p) const {
        assert(p >= 0);
        Mint a = *this, result = 1;
        while (p > 0) {
            if (p & 1)
                result *= a;

            a *= a;
            p >>= 1;
        }
        return result;
    }
    friend ostream& operator << (ostream &stream, const Mint &m) {
        return stream << m.val;
    }
    friend istream& operator >> (istream &stream, Mint &m) {
        return stream >> m.val;
    }
};