# Field Manual for Hackers

## java array | To convert decimal to binary using arrays

1. import java.util.Scanner;

class Test1{
public static void main(String a[]){
int ar[]=new int[10];
int i=0,decimal_number,rem=0;
System.out.print("Enter the decimal number: ");
Scanner o=new Scanner(System.in);
decimal_number=o.nextInt();
while(decimal_number!=0){
rem=decimal_number%2;
decimal_number/=2;
if(i==0){
ar[i]=rem;
}
else{
for(int j=i;j>0;j--){
ar[j]=ar[j-1];
ar[j-1]=rem;
}
}
i++;
}
System.out.print("The binary number is: ");
for(int k=0;k<i;k++)
System.out.print(ar[k] );

}
}

OUTPUT
Enter the decimal number: 17
The binary number is: 10001

2. import java.util.Scanner;
class a
{
public static void main(String args[])
{
Scanner obj=new Scanner(System.in);
int num;
num=obj.nextInt();
int arr[]=new int[];
int i=0;
while(num>0)
{
arr[i]=num%2;
num=num/2;
i++;
}
for(i=i-1;i>=0;i--)
{
System.out.println(arr[i]);
}
}
}

3. import java.util.*;
class DecimalArray
{
public static void main(String args[])
{int Decimal,i=0;
Scanner scan=new Scanner(System.in);
System.out.println("Enter the Decimal Value");
Decimal=scan.nextInt();
int ar[]=new int[10];
while(Decimal>0)
{
ar[i]=Decimal%2;
Decimal=Decimal/2;
i++;
}
System.out.print("Binary Number is ");
for (int j=i-1;j>=0;j--)
{
System.out.print(ar[j]);
}

}
}

4. import java.util.Scanner;
class DBarray{
public static void main(String args[]){
int number,digit=0,remainder=0,i=0;
int ar[]=new int[10];
Scanner scan=new Scanner(System.in);
System.out.println("Enter the number");
number=scan.nextInt();
while(number>0)
{
remainder=number%2;
number=number/2;
ar[i++]=remainder;
}
while(i>0){
System.out.print(ar[--i]);
}
}
}

5. import java.util.Scanner;

class Binary{
public static void main(String ar[]){

int num,rem=0,i=0;
System.out.print("Enter the decimal number: ");
Scanner scan=new Scanner(System.in);
num=scan.nextInt();
int a[]=new int[10];
while(num>0){
rem=num%2;
num=num/2;
a[i]=rem;
i++;

}
System.out.print("The binary number is: ");
for(int j=i-1;j>=0;j--){
System.out.print(a[j]);
}
}//End of main
}//End of class