用C++作答。设计一个求两个大整数四则运算的类。要求如下。 (1)类中私有数据成员为2个运算数及位数、运算结果。 (2)公有成员函数包括:构造函数和析构函数;接收数据的函数;和函数;差函数; 积函数;除函数;显示函数;清零函数等。 程序运行结果如下所示: Please enter one: 1234567 please enter two: 2345678 one+two=3580245 one-two=-1111111 one*two=2895896651426 one/two=52631742743

以下是实现上述功能的C++代码：

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

class BigNum {
private:
    char num1[1000], num2[1000], result[1000];
    int len1, len2, lenr;
public:
    BigNum() {
        len1 = len2 = lenr = 0;
        memset(num1, 0, sizeof(num1));
        memset(num2, 0, sizeof(num2));
        memset(result, 0, sizeof(result));
    }
    ~BigNum() {}
    void input() {
        cout << "Please enter one: ";
        cin >> num1;
        len1 = strlen(num1);
        cout << "Please enter two: ";
        cin >> num2;
        len2 = strlen(num2);
    }
    void add() {
        int i = len1 - 1, j = len2 - 1, k = 0, carry = 0;
        while (i >= 0 || j >= 0) {
            int x = i >= 0 ? num1[i] - '0' : 0;
            int y = j >= 0 ? num2[j] - '0' : 0;
            int sum = x + y + carry;
            result[k++] = sum % 10 + '0';
            carry = sum / 10;
            i--; j--;
        }
        if (carry) result[k++] = carry + '0';
        lenr = k;
    }
    void sub() {
        int i = len1 - 1, j = len2 - 1, k = 0, borrow = 0;
        while (i >= 0 || j >= 0) {
            int x = i >= 0 ? num1[i] - '0' : 0;
            int y = j >= 0 ? num2[j] - '0' : 0;
            int diff = x - y - borrow;
            if (diff < 0) {
                diff += 10;
                borrow = 1;
            } else {
                borrow = 0;
            }
            result[k++] = diff + '0';
            i--; j--;
        }
        while (k > 1 && result[k - 1] == '0') k--;
        lenr = k;
    }
    void mul() {
        int i, j, k, carry = 0;
        for (k = 0; k < len1 + len2; k++) {
            result[k] = '0';
        }
        for (i = 0; i < len1; i++) {
            for (j = 0; j < len2; j++) {
                int x = num1[i] - '0';
                int y = num2[j] - '0';
                int z = x * y + carry + result[i + j] - '0';
                result[i + j] = z % 10 + '0';
                carry = z / 10;
            }
            while (carry) {
                int z = carry + result[i + j] - '0';
                result[i + j] = z % 10 + '0';
                carry = z / 10;
                j++;
            }
        }
        k = len1 + len2 - 1;
        while (k > 1 && result[k] == '0') k--;
        lenr = k + 1;
    }
    void div() {
        int i, j, k;
        for (i = 0; i < len1; i++) {
            result[i] = num1[i];
        }
        result[len1] = '\0';
        lenr = len1;
        while (lenr > 0) {
            for (k = 0; k < 10; k++) {
                if (strcmp(result, num2) < 0) break;
                sub();
            }
            result[lenr] = '0';
            lenr++;
            for (i = lenr - 1; i >= 1; i--) {
                result[i] = result[i - 1];
            }
            result[0] = k + '0';
            if (result[lenr - 1] == '0') lenr--;
        }
    }
    void display() {
        cout << "one+two=";
        for (int i = lenr - 1; i >= 0; i--) {
            cout << result[i];
        }
        cout << endl;
    }
    void clear() {
        len1 = len2 = lenr = 0;
        memset(num1, 0, sizeof(num1));
        memset(num2, 0, sizeof(num2));
        memset(result, 0, sizeof(result));
    }
};

int main() {
    BigNum num;
    num.input();
    num.add();
    num.display();
    num.clear();
    num.input();
    num.sub();
    num.display();
    num.clear();
    num.input();
    num.mul();
    num.display();
    num.clear();
    num.input();
    num.div();
    num.display();
    return 0;
}

上述代码实现了大整数的加减乘除四则运算，并且可以在控制台中输入两个大整数进行运算，并输出结果。