我的计算器

import java.util.Scanner;
public class Calculate {

    /**
     * 吴家晨
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
            int num;
            Scanner s=new Scanner(System.in);
            System.out.print("请输入第一位数：");
            int num1=s.nextInt();
            int num2=s.nextInt();
            System.out.print("请输入运算符：");
            char ch = s.next().charAt(0);
            switch(ch)
            {
            case ‘+‘:
                num=num1+num2;
                break;
            case ‘-‘:
                num=num1-num2;
                break;
            case ‘*‘:
                num=num1*num2;
                break;
            case ‘/‘:
                num=num1/num2;
                break;
            }
            
    
    System.out.print("num");
}
}