Question

请求帮忙修改一段JAVA程序

输入任意2个数和运算符 实现四则运算
输入运算符这块不知道怎么弄 求高手帮忙修改
import java.io.*;//
public class OperatorClass{
public static void main(String args[])throws IOException{
int a,b,c;
BufferedReader buf;
String str;
buf=new BufferedReader(new InputStreamReader(System.in));
System.out.println("请输入a");
str = buf.readLine();
a=Integer.parseInt(str);
System.out.println("请输入b");
str = buf.readLine();
b=Integer.parseInt(str);
System.out.println("请输入运算符号");
str = buf.readLine();
char oper='c';
switch (oper) {
case '+':
System.out.println(a+"+"+b+"="+(a+b)); break;
case '-':
System.out.println(a+"-"+b+"="+(a-b)); break;
case '*':
System.out.println(a+"*"+b+"="+(a*b)); break;
case '/':
System.out.println(a+"/"+b+"="+((float)a/b)); break;
default:
System.out.println("Unknown operator!!");
}
}
}

Answer 1

//刚学的时候我也写过，我就不改啥了，指出你的错误吧，你看看哪里错了
import java.io.*;//
public class OperatorClass{
public static void main(String args[])throws IOException{
int a,b,c;
BufferedReader buf;
String str;
buf=new BufferedReader(new InputStreamReader(System.in));
System.out.println("请输入a");
str = buf.readLine();
a=Integer.parseInt(str);
System.out.println("请输入b");
str = buf.readLine();
b=Integer.parseInt(str);
System.out.println("请输入运算符号");
str = buf.readLine();
///////here
c = str.charAt(0);
switch (c) {
case '+':
System.out.println(a+"+"+b+"="+(a+b)); break;
case '-':
System.out.println(a+"-"+b+"="+(a-b)); break;
case '*':
System.out.println(a+"*"+b+"="+(a*b)); break;
case '/':
System.out.println(a+"/"+b+"="+((float)a/b)); break;
default:
System.out.println("Unknown operator!!");
}
}
}