C++ 简易计算器用函数实现

下面是使用函数实现的 C++ 简易计算器代码示例：

#include <iostream>
using namespace std;

double add(double num1, double num2) {
    return num1 + num2;
}

double subtract(double num1, double num2) {
    return num1 - num2;
}

double multiply(double num1, double num2) {
    return num1 * num2;
}

double divide(double num1, double num2) {
    if (num2 == 0) {
        cout << "Error! Division by zero" << endl;
        exit(0);
    }
    return num1 / num2;
}

int main() {
    char op;
    double num1, num2, result;

    cout << "Enter operator (+, -, *, /): ";
    cin >> op;

    cout << "Enter two operands: ";
    cin >> num1 >> num2;

    switch(op) {
        case '+':
            result = add(num1, num2);
            break;

        case '-':
            result = subtract(num1, num2);
            break;

        case '*':
            result = multiply(num1, num2);
            break;

        case '/':
            result = divide(num1, num2);
            break;

        default:
            cout << "Error! Operator is not correct";
            exit(0);
    }

    cout << num1 << " " << op << " " << num2 << " = " << result << endl;
    return 0;
}

这段代码将加、减、乘、除操作封装成了四个函数，使代码更加模块化和可读性更高。同时，对除数为零的情况进行了处理，避免了程序崩溃。