Welcome To The World Of Java

This site will teach you the basics of Java. It is not necessary to have any prior programming experience.

import java.util.Scanner;
public class Series 
{
 public static void main(String[] args) 
 {
  Scanner sc = new Scanner(System.in);
  System.out.println("Enter the no of terms ");
  int n = sc.nextInt();
  double sum = 0;
  for (int i = 1; i <= n; i++)
   sum = sum + (double) 1 / Math.pow(i, 2);
  System.out.println("Sum of series = " + sum);
 }
}

Output:
Enter the no of terms 
5
Sum of series = 1.4636111111111112
BUILD SUCCESSFUL (total time: 2 seconds)


 import java.util.Scanner;
public class Series  
{
 public static void main(String[] args) 
 {
  Scanner sc = new Scanner(System.in);
  System.out.println("Enter the no of terms ");
  int n = sc.nextInt();
  int sum = 0, i = 0;
  for (int j = 1; j <= n; j++) 
  {
   for (i = 1; i <= j; i++) 
   {
    sum = sum + i;
   }
   i = 1;
  }
  System.out.println("Sum of series = " + sum);
 }
}

Output:
Enter the no of terms 
4
Sum of series = 20
BUILD SUCCESSFUL (total time: 2 seconds)

 import java.util.Scanner;
public class  Series 
{
 public static void main(String[] args) 
 {
  Scanner sc = new Scanner(System.in);
  double sum = 0;
  System.out.println("Enter the no of terms ");
  int n = sc.nextInt();
  for (int i = 1; i <= n; i++) 
  {
   if (i % 2 == 0) {
    sum = sum - (double) 1 / (i * i * i);
   } else {
    sum = sum + (double) 1 / (i * i * i);
   }
  }
  System.out.println(" Sum of the series : " + sum);
 }
}

Output:

Enter the no of terms 
5
Sum of the series : 0.904412037037037
BUILD SUCCESSFUL (total time: 3 seconds)
import java.util.Scanner;
public class Series  
{
 public static void main(String args[])
 {
  Scanner sc = new Scanner(System.in);
  System.out.print("Enter the number of terms: ");
  int n = sc.nextInt();
  int s = 0, c;                                          // s for terms of series, c for n terms
  for (c = 1; c <= n; c++)                          // To generate n terms
  {
   s = s * 10 + 1;
   System.out.print(s + " ");
  }                                                           //for  ends
 }
}


Output:
Enter the number of terms: 7
1, 11, 111, 1111, 11111, 111111, 1111111...... 
BUILD SUCCESSFUL (total time: 3 seconds)
import java.util.Scanner;
public class Series 
{
 public static void main(String args[]) 
 {
  Scanner sc = new Scanner(System.in);
  System.out.print("Enter the number of terms: ");
  int n = sc.nextInt();
  int s = 0, c;                       // s for terms of series, c for counter to generate n terms
  for (c = 1; c <= n; c++) {
   s = s * 10 + c;
   System.out.print(s + " ");
  }
 }
}


Output:
Enter the number of terms: 6
1,  12,  123,  1234,  12345,  123456....... 
BUILD SUCCESSFUL (total time: 3 seconds)
import java.util.Scanner;
public class OddSeries 
{
 public static void main(String args[]) 
  {
  Scanner sc = new Scanner(System.in);
  System.out.print("Enter the number of terms: ");
  int n = sc.nextInt();
  int i = 1, c, f = 1;                            // i for odd nos, c for counter, f for flag
  for (c = 1; c <= n; c++) {
   if (f % 2 == 0) {
    System.out.print(-i + " ");
   } else {
    System.out.print(i + " ");
   }
   i += 2;
   f++;
  }                                                  //Loop ends
 }
}


Output:

Enter the number of terms: 6
1  -3  5  -7  9  -11...... 
BUILD SUCCESSFUL (total time: 6 seconds)

import java.util.Scanner;
public class Series 
{
 public static void main(String args[]) {
  Scanner sc = new Scanner(System.in);
  int c, i = 2, n;                                          // c for counter, i for even nos.
  System.out.print("Enter the number of terms: ");
  n = sc.nextInt();
  System.out.print("\n");
  for (c = 1; c <= n; c++, i += 2)               //to generate n terms of the series
  {
   if (i % 4 == 0) {
    System.out.print(-i + " ");
   } else {
    System.out.print(i + " ");
   }
  }
 }
}

Output:

Enter the number of terms: 10
2 -4 6 -8 10 -12 14 -16 18 -20 
BUILD SUCCESSFUL (total time: 6 seconds)

A tribonacci series is one in which the sum next term is the sum of previous three terms
Example 0 1 2 3 6 11 20………….

import java.util.Scanner;
public class Tribonacci 
 {
 public static void main(String args[]) {
  func(10);
 }
 static void func(int n) {
  int a = 0, b = 1, c = 2, d = 0, i;
  System.out.print(a + " , " + b + " , " + c);
  for (i = 4; i <= n; i++) {
   d = a + b + c;
   System.out.print(", " + d);
   a = b;
   b = c;
   c = d;
  }
 }
}

Output:

0 , 1 , 2, 3, 6, 11, 20, 37, 68, 125
BUILD SUCCESSFUL (total time: 1 second)
A fibonacci series is one in which the next term is the sum of previous two terms
Example. 0 1 1 2 3 5 8……


import java.util.Scanner;
public class Fibonacci 
{
 public static void main(String args[]) {
  func(10);
 }
 static void func(int n) {
  int a = 0, b = 1, c = 0, i;
  System.out.print(a + " , " + b);
  for (i = 3; i <= n; i++) {
   c = a + b;
   System.out.print(", " + c);
   a = b;
   b = c;
  }
 }
}

Output:

0 , 1, 1, 2, 3, 5, 8, 13, 21, 34
BUILD SUCCESSFUL (total time: 0 seconds)