写一个计算器
要求实现加减乘除功能，并且能够循环接收新的数据，通过用户交互实现。
思路：
1.写4个方法：加减乘除
2.利用循环+switch进行用户交互
3.传递需要操作的两个数
4.输出结果
import java.util.Scanner;
public class computer {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
computer computer = new computer();
int intNum1 = 0;
int intNum2 = 0;
float floatNum1 = 0.0f;
float floatNum2 = 0.0f;
String num1 = "";
String num2 = "";
String sign = "请检查运算符号输入是否正确!";
System.out.println("请输入第一个数：");
if(scanner.hasNextInt()){
intNum1 = scanner.nextInt();
num1 = String.valueOf(intNum1);
}else if(scanner.hasNextFloat()){
floatNum1 = scanner.nextFloat();
num1 = String.valueOf(floatNum1);
}
System.out.println("请输入 + 或 - 或 * 或 / 任意一个运算符号：");
if(scanner.hasNext()){
sign = scanner.next();
}
System.out.println("请输入第二个数：");
if(scanner.hasNextInt()){
intNum2 = scanner.nextInt();
num2 = String.valueOf(intNum2);
}else if(scanner.hasNextFloat()){
floatNum2 = scanner.nextFloat();
num2 = String.valueOf(floatNum2);
}
int result = 0;
if(judgeIsDecimal(num1) == false) {
switch (sign)
{
case "+":
result = computer.add(Integer.parseInt(num1), Integer.parseInt(num2));
break;
case "-":
result = computer.sub(Integer.parseInt(num1), Integer.parseInt(num2));
break;
case "*":
result = computer.mul(Integer.parseInt(num1), Integer.parseInt(num2));
break;
case "/":
result = computer.div(Integer.parseInt(num1), Integer.parseInt(num2));
break;
default:
System.out.println("请检查运算符号输入是否正确!");
}
}else if(judgeIsDecimal(num1) == true){
switch (sign)
{
case "+":
result = computer.add(Integer.parseInt(num1), Integer.parseInt(num2));
break;
case "-":
result = computer.sub(Integer.parseInt(num1), Integer.parseInt(num2));
break;
case "*":
result = computer.mul(Integer.parseInt(num1), Integer.parseInt(num2));
break;
case "/":
result = computer.div(Integer.parseInt(num1), Integer.parseInt(num2));
break;
default:
System.out.println("请检查运算符号输入是否正确!");
}
}else {
System.out.println("请检查输入是否为整数或小数!");
}
System.out.println(intNum1+" "+sign+" "+intNum2+" = "+result);
scanner.close();
}
public static boolean judgeIsDecimal(String num){
boolean isdecimal = false;
if (num.contains(".")) {
isdecimal=true;
}
return isdecimal;
}
public static int add(int a,int b){
int result = a + b;
return result;
}
public static float add(float a,float b){
float result = a + b;
return result;
}
public static int sub(int a,int b){
int result = a - b;
return result;
}
public static float sub(float a,float b){
float result = a - b;
return result;
}
public static int mul(int a,int b){
int result = a * b;
return result;
}
public static float mul(float a,float b){
float result = a * b;
return result;
}
public static int div(int a,int b){
int result = a / b;
return result;
}
public static float div(float a,float b){
float result = a / b;
return result;
}
}