Example of Scanner Class

Pattern Programs In Java – Pattern 1

Q. Write a Java program to print given pattern.

Pattern 1 :

1
1 2
1 2 3
1 2 3 4
1 2 3 4 5
1 2 3 4 5 6
1 2 3 4 5 6 7

 

Java Program:

[sourcecode language=”java”]

import java.util.Scanner;

public class MainClass

{

public static void main(String[] args)

{

Scanner sc = new Scanner(System.in);

//Taking rows value from the user

System.out.println("How many rows you want in this pattern?");

int rows = sc.nextInt();

System.out.println("Here is your pattern….!!!");

for (int i = 1; i <= rows; i++)

{

for (int j = 1; j <= i; j++)

{

System.out.print(j+" ");

}

System.out.println();

}

//Close the resources

sc.close();

}

}

[/sourcecode]

Java Program to convert Decimal to Binary

Objectives :

  • Decimal to Binary Conversion
  • Converting Decimal to Binary
  • Converting Decimal Number to Binary format
  • Write a program to convert decimal to binary
  • Write a program to convert decimal number to binary format
  • Write a program to convert positive decimal number to binary format
  • Write a program to convert decimal to binary using Scanner class
  • Write a program to convert decimal to binary, take input using Scanner class

 

Java Program to convert Decimal to Binary : 

[sourcecode lang=”java”]
public class DecimalToBinary {

public void toBinary(int number){
int binary[] = new int[25];
int n = 0;
// Convert Decimal to Binary
while(number > 0){
binary[n++] = number%2;
number = number/2;
}
// Print Binary number
for(int i = n-1;i >= 0;i–){
System.out.print(binary[i]);
}
}

public static void main(String[] args){
DecimalToBinary obj = new DecimalToBinary();
obj.toBinary(14);
}
}
[/sourcecode]

Output :

1110

 

Java Program to convert Decimal to Binary using Scanner class :

[sourcecode lang=”java”]

import java.util.Scanner;

public class DecimalToBinary {

public void toBinary(int number){
int binary[] = new int[14];
int n = 0;

// Convert Decimal to Binary
while(number > 0){
binary[n++] = number%2;
number = number/2;
}

// Print Binary Number
for(int i = n-1;i >= 0;i–){
System.out.print(binary[i]);
}
}

public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print("Enter a number: ");
int num= scanner.nextInt();
DecimalToBinary obj = new DecimalToBinary();
obj.toBinary(num);

}
}

[/sourcecode]

Output :

Enter a number: 14

1110

Program to find Sum of Digits in Java

Objectives :

  • Write a program to compute sum of digits of a given number.
  • Write a program to find sum of digits of a given number.
  • Write a program to calculate sum of digits of a given number.
  • Write a program to compute sum of digits of a given integer number.
  • Write a program to compute sum of digits of a number entered via Command Line.
  • Write a program to compute sum of digits of a given number. Take input from Command Line.
  • Write a program to compute sum of digits of a given number. Take input using Scanner class.

Following is the Java Program to compute Sum of Digits of a given integer number;

Method 1 : Java Program to find Sum of Digits when number is entered from command line

[sourcecode lang=”java”]

class SumOfDigits
{
public static void main(String args[])
{
int n;
int a=0;
int sum=0;

//taking integer number from command line and parsing the same
n=Integer.parseInt(args[0]);

while(n!=0)
{
a=n%10;
n=n/10;
sum=sum+a;
}
System.out.println("Sum of digits: " + sum);
}
}

[/sourcecode]

Steps to run above program via command line :

  1. Compilation : C:\JavaPrograms>javac SumOfDigits.java
  2. Interpretation : C:\JavaPrograms>java SumOfDigits 12345

Output : Sum of digits: 15

Method 2 : Java Program to find Sum of Digits if input is taken using Scanner class

[sourcecode lang=”java”]

import java.util.Scanner;

public class SumOfDigits {
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
int n;
int a=0;
System.out.print("Enter a positive number: ");
n = in.nextInt();

if (n <= 0)
System.out.println("You have entered a negative number.");
else {
int sum = 0;

while (n != 0) {

a=n%10;
n=n/10;
sum=sum+a;
}
System.out.println("Sum of digits: " + sum);
}
}
}

[/sourcecode]

Steps to run above program via command line :

  1. Compilation : C:\JavaPrograms>javac SumOfDigits.java
  2. Interpretation : C:\JavaPrograms>java SumOfDigits 12345

Output :

Trial 1 : With positive number

Enter a positive number: 12345

Sum of digits: 15

Trial 2 : With negative number

Enter a positive number: -12345

You have entered a negative number.