//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

//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

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