A program to print the longest common substring of the two given strings (Java)

//This Java program accepts two strings
//from the user and then prints the longest common
//substring of the two given strings.
//SUBSTRING: A substring of a string is a string that can
//be obtained by removing some characters from
//the beginning or the end of the given string. For example
// "uter" is a substring of "computer".
//
//Sample Output of program :-
/*
Enter the two strings :
i like computer
put it down

Longest Common Substring is :-
put
*/

import java.util.*;
class longestCommonSubstring
{
public static void main()
{
    System.out.println("Enter the two strings : ");
    String a,b;
    Scanner sc=new Scanner(System.in);
    a=sc.nextLine();
    b=sc.nextLine();
    int m=a.length();
    int n=b.length();
    int ar[][]=new int[m+1][n+1];
    int i;
    int j;
    for(i=0;i<m+1;i++)   
    for(j=0;j<n+1;j++)
    ar[i][j]=0;
   
   
    int l=0,x=0,y=0;
    for(i=1;i<m+1;i++)
    {
        for(j=1;j<n+1;j++)
        {
            if(a.charAt(i-1)==b.charAt(j-1))
            {
                ar[i][j]=ar[i-1][j-1]+1;
                if(ar[i][j]>=l)
                {
                    l=ar[i][j];  //l holds value of the largest number in the square which
                    x=i;         //is also the length of longest substring.x and y store its
                    y=j;         //co-ordinates.
                }
            }
        }
    }
   
    String lcs="";
    int k=0;
    for(i=l;i>=1;i--)     //Storing the largest common substring
    {
        if(ar[x][y]!=0)
        {
            lcs=a.charAt(x-1)+lcs;
            x--;y--;
        }
    }
    System.out.println("\nLongest Common Substring is :-");
    System.out.println(lcs);          //Printing the largest common substring
}
}

//Author : Mayank Rajoria

A Java program to find the length of the longest non decreasing subsequence from a group of integers (Java)

//This Java program first accepts a number from the user
//and then accepts that many integers. The program then, using
//dynamic programming, finds the length of the longest
//subsequence of integers such that they are not in
//decreasing order.
//SEQUENCE : A subsequence is a sequence that can
//be derived from another sequence by deleting some
//elements without changing the order of the remaining
//elements. For example, the sequence <1,4,6> is a
//subsequence of <2,1,5,6,4,7,6>.

//Sample Output :-
/*Enter number of integers : 8
Enter the integers :-

-2
5
3
4
10
7
9
12

Longest non-decreasing sequence is of length : 6
*/

import java.util.*;
class longestNonDecreasingSequence
{
public static void main()
{
    int n;
    System.out.print("Enter number of integers : ");
    Scanner sc=new Scanner(System.in);
    n=sc.nextInt();
    int a[]=new int[n];
    int i;
    System.out.println("Enter the integers :-\n");
    for(i=0;i<n;i++)a[i]=sc.nextInt();
    int s[]=new int[n];
    for(i=0;i<n;i++)s[i]=1;
   
    int j,k=0;
    for(i=0;i<n;i++)
    {
        for(j=0;j<i;j++)
        {
            if(a[i]>=a[j])
            {
                k=s[j]+1;
                if(s[i]<=k)
                {
                    s[i]=k;
                }
            }
        }
    }
    int ans=a[0];;
    for(i=0;i<n;i++)
    {
        if(s[i]>=ans)
        {
            ans=s[i];
        }
    }
    System.out.print("\nLongest non-decreasing sequence is of length : "+ans);
}
}

//Author : Mayank Rajoria

Printing a pyramid pattern of digits #12

//This java program accepts a number of user
//which tells the program that how many lines
//of the pattern will be printed.
/*Sample Input :6
Sample Output :
                0
             1 0 1
          2 1 0 1 2
       3 2 1 0 1 2 3
    4 3 2 1 0 1 2 3 4
 5 4 3 2 1 0 1 2 3 4 5   */

import java.util.*;
class pattern
{
public static void main()
{
    System.out.println("Enter a number");
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    int i,j;
    for(i=0;i<=n;i++)
    {
        for(j=0;j<=(2*(n-i));j++)
        {
            System.out.print(" ");
        }
       
        for(j=i;j>=0;j--)
        {
            System.out.print(j+" ");
        }
       
        for(j=1;j<=i;j++)
        {
            System.out.print(j+" ");
        }
        System.out.println();
    }
}
}

//Author : Mayank Rajoria

Using Selection Sort to sort an array (Java)

//This Java program depicts the use of Selection
//sort technique to arrange the integers in
//an array in ascending order.

import java.util.*;
class selectionSort
{
static void main()
{
    Scanner sc=new Scanner(System.in);
    System.out.println("Enter 10");
    int a[]=new int[10];
    int i;
    for(i=0;i<10;i++)
    {
        a[i]=sc.nextInt();
    }
    int min=0,j,k;

    for(i=0;i<10;i++)
    {
        for(j=i;j<10;j++)
        {
            if(a[i]>a[j])
            {
                k=a[i];
                a[i]=a[j];
                a[j]=k;
            }
        }
    }

    for(i=0;i<10;i++)
    {
        System.out.println(a[i]);
    }
}
}

//Author : Mayank Rajoria

Using Bubble Sort for an array (Java)

//This Java program depicts the use of Bubble
//sort technique to arrange the integers in
//an array in ascending order.

import java.util.*;
class bubbleSort
{
static void main()
{
    Scanner sc=new Scanner(System.in);
    System.out.println("Enter 10 numbers :-");
    int a[]=new int[10];
    int i;
    for(i=0;i<10;i++)
    {
        a[i]=sc.nextInt();   //Accepting numbers
    }
    int min=0,j,k;

    for(i=0;i<10;i++)
    {
        for(j=0;j<9-i;j++)
        {
            if(a[j]>a[j+1])
            {
                k=a[j];           
                a[j]=a[j+1];   
                a[j+1]=k;      
            }
        }
    }

    for(i=0;i<10;i++)
    {
        System.out.println(a[i]); //Printing the numbers
    }
}
}

//Author : Mayank Rajoria

Printing a pyramid pattern of digits #11

//This java program accepts a number of user
//which tells the program that how many lines
//of the pattern will be printed.
/*Sample Input :6
Sample Output :
1
22
333
4444
55555
666666   */


import java.util.*;
class pattern
{
public static void main()
{
    System.out.print("Enter the number of lines you want: ");
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    int i,j,k=1;
    for(i=1;i<=n;i++,k+=2)
    {
        for(j=1;j<=i;j++)
        {
            System.out.print(i);
        }
        System.out.println();
    }
}
}

//Author: Mayank Rajoria

Printing a dual pyramid pattern of '*' #4

//This java program accepts a number of user
//which tells the program that how many lines
//of the pattern will be printed.
/*Sample Input :7
Sample Output :

            *
          *A*
        *A*A*
      *A*A*A*
    *A*A*A*A*
  *A*A*A*A*A*
*A*A*A*A*A*A*   */



import java.util.*;
class pattern
{
public static void main()
{
    System.out.print("Enter the number of lines you want: ");
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    int i,j,k=1;
    for(i=1;i<=n;i++,k+=2)
    {
        for(j=n;j>i;j--)
        {
            System.out.print(" ");
        }
        for(j=1;j<=k;j++)
        {
            if(j%2==0)
            {
                System.out.print("A");
            }
            else
            {
                System.out.print("*");
            }
        }
        System.out.println();
    }
}
}

//Author: Mayank Rajoria

Printing a pyramid pattern of digits #10

//This java program accepts a number of user
//which tells the program that how many lines
//of the pattern will be printed.
/*Sample Input :7
Sample Output :

1234567
  123456
    12345
      1234
        123
          12
            1  */

import java.util.*;
class pattern
{
public static void main()
{
    System.out.print("Enter the number of lines you want: ");
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    int i,j,k=1;
    for(i=n;i>=1;i--,k++)
    {
        for(j=1;j<k;j++)
        {
            System.out.print(" ");
        }
        for(j=1;j<=i;j++)
        {
            System.out.print(j);
        }
        System.out.println();
    }
}
}

//Author : Mayank Rajoria

Happy Diwali

Wishing all my fellow blog readers a very very Happy Diwali. Diwali, the festival of lights, commemorates Lord Rama's return to his kingdom of Ayodhya after completing 14 years' exile.
May this festival bring happiness to all your homes...

Printing a pyramid pattern of digits #9

//This java program accepts a number of user
//which tells the program that how many lines
//of the pattern will be printed and then prints
//the pattern of the given number of lines.
/*Sample Input : 7

Sample Output :
            7
          767
        76567
      7654567
    765434567
  76543234567
7654321234567 */
//For a left aligned version of this pattern
//visit: Java Programs: Printing a pyramid pattern of digits 8 (Java)

import java.util.*;
class pattern
{
public static void main()
{
    System.out.print("Enter the number of lines you want : ");
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    int i,j,k=n,l=1;
    for(i=1;i<=n;i++)
    {
        for(j=n;j>=i+1;j--)
        {
            System.out.print(" ");
        }
        k=n;
        for(j=1;j<=i;j++,k--)
        {
            System.out.print(k);
        }
        k=k+2;
        for(j=1;j<=i-1;j++,k++)
        {
            System.out.print(k);
        }
        System.out.println();
    }
}
}
//Author : Mayank Rajoria