高精度运算

#include <iostream>#include <iomanip>#include <algorithm>#include <cassert>#include <vector>using namespace std;typedef long long int64;const int B = 1000000000;const int L = 9;inline int intcmp(int a, int b){    if (a > b)        return 1;    else if (a < b)        return -1;    else        return 0;}struct BigInt{    vector<int> a;    BigInt(){}    BigInt(int n)    {        while (n > 0)            a.push_back(n % B), n /= B;    }    BigInt(int64 n)    {        while (n > 0)            a.push_back(n % B), n /= B;    }    inline void clr0()    {        while (!a.empty() && a.back() == 0)            a.pop_back();    }    inline BigInt &operator+=(const BigInt &rhs)    {        a.resize(max(a.size(), rhs.a.size()));        int t = 0;        for (int i = 0; i < (int)rhs.a.size(); i++)        {            a[i] += rhs.a[i] + t;            t = a[i] >= B;            a[i] -= B & (-t);        }        for (int i = (int)rhs.a.size(); t != 0 && i < (int)a.size(); i++)        {            a[i] += t;            t = a[i] >= B;            a[i] -= B & (-t);        }        if (t != 0)            a.push_back(t);        return *this;    }    inline BigInt &operator-=(const BigInt &rhs)    {        a.resize(max(a.size(), rhs.a.size()));        int t = 0;        for (int i = 0; i < (int)rhs.a.size(); i++)        {            a[i] -= rhs.a[i] + t;            t = a[i] < 0;            a[i] += B & (-t);        }        for (int i = (int)rhs.a.size(); t != 0 && i < (int)a.size(); i++)        {            a[i] -= t;            t = a[i] < 0;            a[i] += B & (-t);        }        clr0();        return *this;    }    inline BigInt &operator*=(const BigInt &rhs)    {        int na = (int)a.size();        a.resize(na + rhs.a.size());        for (int i = na - 1; i >= 0; i--)        {            int ai = a[i];            int64 t = 0;            a[i] = 0;            for (int j = 0; j < (int)rhs.a.size(); j++)            {                t += a[i + j] + (int64)ai * rhs.a[j];                a[i + j] = t % B;                t /= B;            }            for (int j = (int)rhs.a.size(); t != 0 && i + j < (int)a.size(); j++)            {                t += a[i + j];                a[i + j] = t % B;                t /= B;            }            assert(t == 0);        }        clr0();        return *this;    }    inline BigInt &operator/=(const BigInt &rhs)    {        return *this = div(rhs);    }    inline BigInt &operator%=(const BigInt &rhs)    {        return div(rhs), *this;    }    inline BigInt &shlb(int l = 1)    {        if (a.empty())            return *this;        a.resize(a.size() + l);        for (int i = (int)a.size() - 1; i >= l; i--)            a[i] = a[i - l];        for (int i = 0; i < l; i++)            a[i] = 0;        return *this;    }    inline BigInt &shrb(int l = 1)    {        for (int i = 0; i < (int)a.size() - l; i++)            a[i] = a[i + l];        a.resize(max((int)a.size() - l, 0));        return *this;    }    inline int cmp(const BigInt &rhs) const    {        if (a.size() != rhs.a.size())            return intcmp(a.size(), rhs.a.size());        for (int i = (int)a.size() - 1; i >= 0; i--)            if (a[i] != rhs.a[i])                return intcmp(a[i], rhs.a[i]);        return 0;    }    inline BigInt div(const BigInt &rhs)    {        assert(!rhs.a.empty());        if (rhs > *this)            return 0;        BigInt q, r;        q.a.resize((int)a.size() - (int)rhs.a.size() + 1);        for (int i = (int)a.size() - 1; i > (int)a.size() - (int)rhs.a.size(); i--)        {            r.shlb();            r += a[i];        }        for (int i = (int)a.size() - (int)rhs.a.size(); i >= 0; i--)        {            r.shlb();            r += a[i];            if (r.cmp(rhs) < 0)                q.a[i] = 0;            else            {                int le = 0, ri = B;                while (le != ri)                {                    int mi = (le + ri) / 2;                    if ((rhs * mi).cmp(r) <= 0)                        le = mi + 1;                    else                        ri = mi;                }                q.a[i] = le - 1;                r -= rhs * q.a[i];            }        }        q.clr0();        *this = r;        return q;    }    friend inline BigInt operator+(const BigInt &lhs, const BigInt &rhs)    {        BigInt res = lhs;        return res += rhs;    }    friend inline BigInt operator-(const BigInt &lhs, const BigInt &rhs)    {        BigInt res = lhs;        return res -= rhs;    }    friend inline BigInt operator*(const BigInt &lhs, const BigInt &rhs)    {        BigInt res = lhs;        return res *= rhs;    }    friend inline BigInt operator/(const BigInt &lhs, const BigInt &rhs)    {        BigInt res = lhs;        return res.div(rhs);    }    friend inline BigInt operator%(const BigInt &lhs, const BigInt &rhs)    {        BigInt res = lhs;        return res.div(rhs), res;    }    friend inline ostream &operator<<(ostream &out, const BigInt &rhs)    {        if (rhs.a.size() == 0)            out << "0";        else        {            out << rhs.a.back();            for (int i = (int)rhs.a.size() - 2; i >= 0; i--)                out << setfill('0') << setw(L) << rhs.a[i];        }        return out;    }    friend inline bool operator<(const BigInt &lhs, const BigInt &rhs)    {        return lhs.cmp(rhs) < 0;    }    friend inline bool operator<=(const BigInt &lhs, const BigInt &rhs)    {        return lhs.cmp(rhs) <= 0;    }    friend inline bool operator>(const BigInt &lhs, const BigInt &rhs)    {        return lhs.cmp(rhs) > 0;    }    friend inline bool operator>=(const BigInt &lhs, const BigInt &rhs)    {        return lhs.cmp(rhs) >= 0;    }    friend inline bool operator==(const BigInt &lhs, const BigInt &rhs)    {        return lhs.cmp(rhs) == 0;    }    friend inline bool operator!=(const BigInt &lhs, const BigInt &rhs)    {        return lhs.cmp(rhs) != 0;    }};

Bigint a;

cout<<a<<endl;