Question

Write an Android phone program such that two instances of EditText with texts “Input a positive integer (smaller)” and “Input a positive integer (larger)”, one instances of Button with text “Click here to get outputs”, and four instances of TextView with respective texts “Decide if the larger one is a multiple of the smaller one : ”, “The GCD of two integers : ”, “The LCM of the two integers : ”,  “The permutations based on two integers : ”, “The combinations based on the two integers : “, and "The definite integral of 3*x*x of from smaller integer to larger integer : " are displayed vertically on the AVD. The users of your program will input two positive integers. After the users click the button, the information or values based on the two input integers will be displayed in the corresponding six instances of TextView.  (Hints: GCD denotes the greatest common divisor and LCM denotes the least common multiple.) 

Answer 1

OUTPUT

Code: MainActivity.class

package cheggans.app;

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

import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {



    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        final EditText etnum1=findViewById(R.id.num1);
        final EditText etnum2=findViewById(R.id.num2);

        final TextView tvcheck=findViewById(R.id.checktv);
        final TextView tvgcd=findViewById(R.id.gcdtv);
        final TextView tvlcm=findViewById(R.id.lcmtv);
        final TextView tvperm=findViewById(R.id.permtv);
        final TextView tvcomb=findViewById(R.id.combtv);
        final TextView tvintg=findViewById(R.id.ingrltv);


        Button btn=findViewById(R.id.button);


        btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                int num1=Integer.parseInt(etnum1.getText().toString());
                int num2=Integer.parseInt(etnum2.getText().toString());


                tvcheck.setText("Decide if the larger one is a multiple of the smaller one :" + checklarger(num1,num2));
                tvgcd.setText("The GCD of two integers :"+getGcd(num1,num2));
                tvlcm.setText("The LCM of the two integers : :"+getLcm(num1,num2));
                tvperm.setText("The permutations based on two integers : "+getPerm(num1,num2));
                tvcomb.setText("The combinations based on the two integers : "+getComb(num1,num2));
                tvintg.setText("The definite integral is :"+getIntegral(num1,num2));


            }
        });


    }


    public int checklarger(int a,int b){
        int c=0;
        if(a>b){
            c=a;
        }
        else{
            c=b;
        }

        return c;
    }



    public int getGcd(int a,int b){
        int n1 = a, n2 = b, gcd = 1;
        for(int i = 1; i <= n1 && i <= n2; ++i)
        {
            // Checks if i is factor of both integers
            if(n1 % i==0 && n2 % i==0)
                gcd = i;
        }

        return gcd;
    }


    public int getLcm(int a,int b){
        int n1 = a, n2 = b, lcm;
        // maximum number between n1 and n2 is stored in lcm
        lcm = (n1 > n2) ? n1 : n2;
        // Always true
        while(true)
        {
            if( lcm % n1 == 0 && lcm % n2 == 0 )
            {
                break;
            }
            ++lcm;
        }


        return lcm;
    }


    static int fact(int n) {
        int fact = 1;
        int i = 1;
        while(i <= n) {
            fact *= i;
            i++;
        }
        return fact;
    }
    public int getPerm(int a,int b){
        return fact(a) / fact(a - b);
    }


    int getComb(int n, int r)
    {
        return fact(n) / (fact(r) *fact(n - r));
    }






    int getIntegral(int a, int b)
    {

        //integral of 3*x*x is   x^3

        int lowerBound= a*a*a;
        int upperBound= b*b*b;


        return upperBound-lowerBound;
    }



}

XML: activity_main

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="91dp"
        android:text="Click here to get outputs"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/num2" />

    <EditText
        android:id="@+id/num2"
        android:layout_width="290dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="29dp"
        android:ems="10"
        android:hint="Input a positive Integer(larger)"
        android:inputType="number"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/num1" />

    <EditText
        android:id="@+id/num1"
        android:layout_width="290dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="100dp"
        android:ems="10"
        android:hint="Input a positive Integer(smaller)"

        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <LinearLayout
        android:id="@+id/textView6"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/button">

        <TextView
            android:id="@+id/checktv"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:padding="5dp"
            android:text="" />

        <TextView
            android:id="@+id/gcdtv"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:padding="5dp"
            android:text="" />

        <TextView
            android:id="@+id/lcmtv"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:padding="5dp"
            android:text="" />

        <TextView
            android:id="@+id/permtv"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:padding="5dp"
            android:text="" />

        <TextView
            android:id="@+id/combtv"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:padding="5dp"
            android:text="" />

        <TextView
            android:id="@+id/ingrltv"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:padding="5dp"
            android:text="" />


    </LinearLayout>

</androidx.constraintlayout.widget.ConstraintLayout>