Arithmetic operator | Type casting

public class MainActivity extends AppCompatActivity {

    TextView textview;
    Button button;
    EditText edittext;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        textview = findViewById(R.id.textview);
        button = findViewById(R.id.button);
        edittext = findViewById(R.id.edittext);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

             int  num1,num2,result;

             num1 = 20;
             num2 = 10;

             // Arithmetic operator | Type casting

                 result = num1+num2;
                 textview.append("reasult = "+result+"\n");

                result = num1-num2;
                textview.append("reasult = "+result+"\n");

                result = num1*num2;
                textview.append("reasult = "+result+"\n");

                result = num1/num2;
                textview.append("reasult = "+result+"\n");

                result = num1 & num2;
                textview.append("reasult = "+result+"\n");

            }
        });

    }

} 

inpute user 

package com.companyname.appname;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    TextView textview;
    Button button;
    EditText edittext;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        textview = findViewById(R.id.textview);
        button = findViewById(R.id.button);
        edittext = findViewById(R.id.edittext);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {


            int num1,num2,num3,num4,num5;

            String in = edittext.getText().toString();
            int inpute = Integer.parseInt(in);

            num1 = inpute + inpute;
            num2 = inpute - inpute;
            num3 = inpute * inpute;
            num4 = inpute / inpute;
            num5 = inpute % inpute;
            

             textview.append("output = "+num1+"\n");
             textview.append("output = "+num2+"\n");
             textview.append("output = "+num3+"\n");
             textview.append("output = "+num4+"\n");
             textview.append("output = "+num5+"\n");

            }
        });

    }
}