c编写一个四则运算计算器程序，从键盘输入任意两个数和一个运算符（+、-、*、/），计算其运算的结果并输出，要求分别使用if和switch语句编程

使用if语句实现：

#include <stdio.h>

int main() {
    float num1, num2, result;
    char operator;

    printf("请输入两个数和运算符（+、-、*、/）：\n");
    scanf("%f %f %c", &num1, &num2, &operator);

    if (operator == '+') {
        result = num1 + num2;
    } else if (operator == '-') {
        result = num1 - num2;
    } else if (operator == '*') {
        result = num1 * num2;
    } else if (operator == '/') {
        if (num2 == 0) {
            printf("除数不能为0！\n");
            return 0;
        }
        result = num1 / num2;
    } else {
        printf("运算符输入错误！\n");
        return 0;
    }

    printf("%.2f %c %.2f = %.2f\n", num1, operator, num2, result);

    return 0;
}

使用switch语句实现：

#include <stdio.h>

int main() {
    float num1, num2, result;
    char operator;

    printf("请输入两个数和运算符（+、-、*、/）：\n");
    scanf("%f %f %c", &num1, &num2, &operator);

    switch (operator) {
        case '+':
            result = num1 + num2;
            break;
        case '-':
            result = num1 - num2;
            break;
        case '*':
            result = num1 * num2;
            break;
        case '/':
            if (num2 == 0) {
                printf("除数不能为0！\n");
                return 0;
            }
            result = num1 / num2;
            break;
        default:
            printf("运算符输入错误！\n");
            return 0;
    }

    printf("%.2f %c %.2f = %.2f\n", num1, operator, num2, result);

    return 0;
}