print_lcs.java

import java.util.Scanner;

class print_lcs {
    public String longestCommonSubsequence(String text1, String text2) {
        int n = text1.length();
        int m = text2.length();
        return LCS(text1,text2,n,m);
    }

    private String LCS (String text1,String text2,int n,int m)
    {

        int[][] t = new int[1001][1001];
        for(int i=0;i<m+1;i++)
        {
            for(int j=0;j<n+1;j++)
            {

                if (i==0 || j==0);
                {
                    t[i][j] = 0;
                }
            }
        }
        for (int i = 1;i<n+1;i++)
        {
            for (int j = 1;j<m+1;j++)
            {
                if (text1.charAt(i-1) == text2.charAt(j-1))
                {
                    t[i][j] = 1+t[i-1][j-1];
                }else{
                    t[i][j] = Math.max(t[i-1][j],t[i][j-1]);
                }
            }
        }

        int i=n;
        int j=m;
        StringBuilder str2  = new StringBuilder();
        while (i>0 && j>0)
        {
            if(text1.charAt(i-1) == text2.charAt(j-1))
            {
                str2.append(text1.charAt(i-1));
                i--;
                j--;
            }else
            {
                if (t[i][j-1] > t[i-1][j])
                {
                    j--;
                }else{
                    i--;
                }
            }


        }
        return  str2.reverse().toString();


    }

    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        String one = s.next();
        String two = s.next();
        print_lcs print_lcs   = new print_lcs();
        System.out.println(print_lcs.longestCommonSubsequence(one , two));
    }


}