高精度运算C++代码

以下是一个简单的高精度加法示例代码，你可以根据需要进行修改和扩展：

#include <iostream>
#include <cstring>
using namespace std;

const int MAXN = 1005;
const int BASE = 10;

struct BigInt {
    int len, s[MAXN];

    BigInt() {
        memset(s, 0, sizeof(s));
        len = 1;
    }

    BigInt(int num) {
        *this = num;
    }

    BigInt(const char* num) {
        *this = num;
    }

    BigInt operator = (int num) {
        char s[MAXN];
        sprintf(s, "%d", num);
        *this = s;
        return *this;
    }

    BigInt operator = (const char* num) {
        memset(s, 0, sizeof(s));
        len = strlen(num);
        for (int i = 0; i < len; i++) s[i] = num[len - i - 1] - '0';
        return *this;
    }

    BigInt operator + (const BigInt& b) const {
        BigInt c;
        c.len = 0;
        for (int i = 0, g = 0; g || i < max(len, b.len); i++) {
            int x = g;
            if (i < len) x += s[i];
            if (i < b.len) x += b.s[i];
            c.s[c.len++] = x % BASE;
            g = x / BASE;
        }
        return c;
    }

    void clean() {
        while (len > 1 && !s[len-1]) len--;
    }

    BigInt operator * (const BigInt& b) const {
        BigInt c; c.len = len + b.len;
        for (int i = 0; i < len; i++)
            for (int j = 0; j < b.len; j++)
                c.s[i+j] += s[i] * b.s[j];
        for (int i = 0; i < c.len-1; i++)
            c.s[i+1] += c.s[i] / BASE, c.s[i] %= BASE;
        c.clean();
        return c;
    }

    BigInt operator - (const BigInt& b) const {
        BigInt c; c.len = 0;
        for (int i = 0, g = 0; i < len; i++) {
            int x = s[i] - g;
            if (i < b.len) x -= b.s[i];
            if (x >= 0) g = 0;
            else g = 1, x += BASE;
            c.s[c.len++] = x;
        }
        c.clean();
        return c;
    }

    bool operator < (const BigInt& b) const {
        if (len != b.len) return len < b.len;
        for (int i = len-1; i >= 0; i--)
            if (s[i] != b.s[i]) return s[i] < b.s[i];
        return false;
    }

    bool operator > (const BigInt& b) const {
        return b < *this;
    }

    bool operator <= (const BigInt& b) const {
        return !(b < *this);
    }

    bool operator == (const BigInt& b) const {
        return !(b < *this) && !(*this < b);
    }

    BigInt operator += (const BigInt& b) {
        *this = *this + b;
        return *this;
    }

    friend istream& operator >> (istream& in, BigInt& x) {
        string s;
        in >> s;
        x = s.c_str();
        return in;
    }

    friend ostream& operator << (ostream& out, const BigInt& x) {
        out << x.s[x.len-1];
        for (int i = x.len-2; i >= 0; i--)
            out << x.s[i];
        return out;
    }
};

int main() {
    BigInt a, b;
    cin >> a >> b;
    cout << a + b << endl;
    return 0;
}

注意：此代码仅作为参考，仍需根据实际情况或需求进行修改和优化。