Question

Please convert this java program to a program with methods please.

import java.io.*;
import java.util.*;

public class Number{

public static void main(String[] args) {
  
Scanner scan = new Scanner(System.in);

System.out.println("Enter 20 integers ranging from -999 to 999 : "); //print statement

int[] array = new int[20]; //array of size 20

for(int i=0;i<20;i++){

array[i] = scan.nextInt(); //user input

if(array[i]<-999 || array[i]>999){ //check if value is inside the range

System.out.println("Please enter a number between -999 to 999");
i--;
}
}

// Now we have to create 4 array for odd,even,positive,negative number

int odd = 0; //initializing as zero
int even = 0;
int positive = 0;
int negative = 0;

for(int i=0;i<20;i++){

if(array[i]%2 == 0){ //check if even

even++; //increment
}
if(array[i]%2 != 0){ //check if odd

odd++; //increment
}
if(array[i]>0){ //check if positive

positive++; //increment
}   
if(array[i]<0){ //check if negative

negative++; //increment
}
}

//Now initializing array for all

int[] oddA = new int[odd]; //arrays of required size
int[] evenA = new int[even];
int[] positiveA = new int[positive];
int[] negativeA = new int[negative];

int countOdd = 0; //initializing as zero
int countEven = 0; //for array indexing
int countPositive = 0;
int countNegative = 0;

for(int i=0;i<20;i++){

if(array[i]%2 == 0){ //check if even

evenA[countEven] = array[i]; //Putting value
countEven++;
}
if(array[i]%2 != 0){ //check if odd

oddA[countOdd] = array[i]; //Putting value
countOdd++;
}
if(array[i]>0){ //check if positive

positiveA[countPositive] = array[i]; //Putting value
countPositive++;   
}   
if(array[i]<0){ //check if negative

negativeA[countNegative] = array[i]; //Putting value
countNegative++;   
}
}

//Difference between highest and lowest positive number

int highest = -1000; //Initialize
int lowest = 1000;

for(int i=0;i<20;i++){

if(array[i]>0 && array[i]>highest){ //condition for highest positive number

highest = array[i];
}
if(array[i]>0 && array[i]<lowest){ //condition for lowest positve number

lowest = array[i];
}
}

int diff = highest - lowest; //difference

//Sum of all negative numbers

int sumNegative = 0;

for(int i=0;i<negative;i++){

sumNegative = sumNegative + negativeA[i]; //sum of negative number
}

int input = 0;

do{

System.out.println("Enter your choice : ");

System.out.println("1. The orginal array");
System.out.println("2. The array of all odd numbers");
System.out.println("3. The array of all even numbers");
System.out.println("4. The array of all positive numbers");
System.out.println("5. The array of all negative numbers");
System.out.println("6. The highest and lowest postive value and difference between them");
System.out.println("7. The sum of all negative numbers");
System.out.println("8. Display all positive appearing in positive array whose value is less than 50");
System.out.println("9. Display all even numbers in reverse order");
System.out.println("10. Display all multiples of 5 (positive or negative)");

int choice = scan.nextInt(); //user choice

switch(choice){

case 1 :

for(int i=0;i<20;i++){

System.out.print(array[i]+" ");
}
System.out.println("");
break;

case 2 :

for(int i=0;i<odd;i++){

System.out.print(oddA[i]+" ");
}
System.out.println("");
break;

case 3 :

for(int i=0;i<even;i++){

System.out.print(evenA[i]+" ");
}
System.out.println("");
break;

case 4 :

for(int i=0;i<positive;i++){

System.out.print(positiveA[i]+" ");
}
System.out.println("");
break;

case 5 :

for(int i=0;i<negative;i++){

System.out.print(negativeA[i]+" ");
}
System.out.println("");
break;

case 6 :

System.out.println("The highest positive value is : " + highest);
System.out.println("The lowest positive value is : " + lowest);
System.out.println("The difference between the highest and lowest positve value is : " + diff);
break;

case 7 :

System.out.println("The sum of all negative number is : " + sumNegative);
break;

case 8 :

for(int i=0;i<positive;i++){

if(positiveA[i]<50){

System.out.print(positiveA[i]+" ");
}
}
System.out.println("");
break;

case 9 :

for(int i=even-1;i>=0;i--){

System.out.print(evenA[i]+" ");
}
System.out.println("");
break;

case 10 :

for(int i=0;i<20;i++){

if(array[i]%5 == 0){

System.out.print(array[i]+" ");
}
}
System.out.println("");
break;
}

System.out.println("Do you wish to continue : (1 or 0) : Press 1 to continue : ");

input = scan.nextInt();

}while(input == 1);
}
}

Answer 1

Solution:

import java.io.*;
import java.util.*;

public class Main{
  
public static int odd = 0, even=0, positive = 0, negative=0;
public static int oddA[], evenA[], positiveA[], negativeA[];
public static int countOdd = 0, countEven = 0, countPositive = 0, countNegative = 0;
public static int highest = -1000, lowest = 1000, sumNegative = 0, diff=0;
public static int[] array = new int[20];
  
static void input(){
  
System.out.println("Enter 20 integers ranging from -999 to 999 : "); //print statement
  
Scanner scan=new Scanner(System.in);
  
for(int i=0;i<20;i++){
array[i] = scan.nextInt(); //user input

if(array[i]<-999 || array[i]>999){ //check if value is inside the range
System.out.println("Please enter a number between -999 to 999");
i--;
}
}
  
}
  
// Now we have to create 4 array for odd,even,positive,negative number
static void create(){

for(int i=0;i<20;i++){

if(array[i]%2 == 0)
even++;
  
if(array[i]%2 != 0)
odd++;
  
if(array[i]>0)
positive++;
  
if(array[i]<0)
negative++;
}
}
  
//Difference between highest and lowest positive number
static void diff(){

for(int i=0;i<20;i++){
  
if(array[i]>0 && array[i]>highest) //condition for highest positive number
highest = array[i];
  
if(array[i]>0 && array[i]<lowest) //condition for lowest positve number
lowest = array[i];
}
  
diff = highest - lowest; //difference
}
  
//Now initializing array for all
static void init(){
  
oddA = new int[odd];
evenA = new int[even];
positiveA = new int[positive];
negativeA = new int[negative];

for(int i=0;i<20;i++){
  
if(array[i]%2 == 0){ //check if even
evenA[countEven] = array[i]; //Putting value
countEven++;
}
  
if(array[i]%2 != 0){ //check if odd
oddA[countOdd] = array[i]; //Putting value
countOdd++;
}
  
if(array[i]>0){ //check if positive
positiveA[countPositive] = array[i]; //Putting value
countPositive++;   
}   
  
if(array[i]<0){ //check if negative
negativeA[countNegative] = array[i]; //Putting value
countNegative++;   
}
}

for(int i=0;i<negative;i++)
sumNegative = sumNegative + negativeA[i]; //sum of negative number
}

public static void main(String[] args) {
  
Scanner scan = new Scanner(System.in);
Main obj= new Main();
obj.input();
obj.create();
obj.init();
obj.diff();

int input = 0;

do{
  
System.out.println("Enter your choice : ");
  
System.out.println("1. The orginal array");
System.out.println("2. The array of all odd numbers");
System.out.println("3. The array of all even numbers");
System.out.println("4. The array of all positive numbers");
System.out.println("5. The array of all negative numbers");
System.out.println("6. The highest and lowest postive value and difference between them");
System.out.println("7. The sum of all negative numbers");
System.out.println("8. Display all positive appearing in positive array whose value is less than 50");
System.out.println("9. Display all even numbers in reverse order");
System.out.println("10. Display all multiples of 5 (positive or negative)");
  
int choice = scan.nextInt(); //user choice

switch(choice){
  
case 1 :
  
for(int i=0;i<20;i++){
System.out.print(array[i]+" ");
}
System.out.println("");
break;
  
case 2 :
  
for(int i=0;i<odd;i++){

System.out.print(oddA[i]+" ");
}
System.out.println("");
break;
  
case 3 :
  
for(int i=0;i<even;i++){
  
System.out.print(evenA[i]+" ");
}
System.out.println("");
break;
  
case 4 :
  
for(int i=0;i<positive;i++){
  
System.out.print(positiveA[i]+" ");
}
System.out.println("");
break;
  
case 5 :
  
for(int i=0;i<negative;i++){
  
System.out.print(negativeA[i]+" ");
}
System.out.println("");
break;
  
case 6 :
  
System.out.println("The highest positive value is : " + highest);
System.out.println("The lowest positive value is : " + lowest);
System.out.println("The difference between the highest and lowest positve value is : " + diff);
break;
  
case 7 :
  
System.out.println("The sum of all negative number is : " + sumNegative);
break;
  
case 8 :
  
for(int i=0;i<positive;i++){
  
if(positiveA[i]<50){
  
System.out.print(positiveA[i]+" ");
}
}
System.out.println("");
break;
  
case 9 :
  
for(int i=even-1;i>=0;i--){
  
System.out.print(evenA[i]+" ");
}
System.out.println("");
break;
  
case 10 :
  
for(int i=0;i<20;i++){
  
if(array[i]%5 == 0)
System.out.print(array[i]+" ");
}
System.out.println("");
break;
}
  
System.out.println("Do you wish to continue : (1 or 0) : Press 1 to continue : ");
input = scan.nextInt();
  
}while(input == 1);
}
}