lcs problem code

LongestCommonSubsequence.java

public class LongestCommonSubsequence {

    public static int getLongestCommonSubsequence(String a, String b) {

        int[][] matrix = new int[a.length() + 1][b.length() + 1];

        for (int i = 0; i <= a.length(); i++) {
            for (int j = 0; j <= b.length(); j++) {
                if (i == 0 || j == 0) {
                    matrix[i][j] = 0;
                } else if (a.charAt(i - 1) == b.charAt(j - 1)) {
                    matrix[i][j] = 1 + matrix[i - 1][j - 1];
                } else {
                    matrix[i][j] = Math.max(matrix[i - 1][j], matrix[i][j - 1]);
                }
            }
        }

        return matrix[a.length()][b.length()];
    }

    public static void main(String[] args) {

        String s1 = "atag";
        String s2 = "atag";

        System.out.println("Length of LCS is" + " " + getLongestCommonSubsequence(s1, s2));
    }

}