public static void main(String[] args) {

        String squence1 = "ABCBDAB";

        String squence2 = "BDCABC";

        int len1 = squence1.length(), len2 = squence2.length();

        if (len1 <= 0 || len2 <= 0) {

            System.out.println("empty squence!");

            return;

        }

        int[][] allCommonSubLen = new int[len1+1][len2+1];

        //print all sub-squences

        String subSquence = "";

        //初始化i=0, j=0

        for (int i = 0; i < len1; i++) {

            allCommonSubLen[i][0] = 0;

        }

        for (int j = 0; j < len2; j++) {

            allCommonSubLen[0][j] = 0;

        }

        //迭代关系

        for (int i = 1; i <= len1; i++) {

            for (int j = 1; j <= len2; j++) {

                char c1 = squence1.charAt(i-1);

                char c2 = squence2.charAt(j-1);

                if (c1 == c2) {

                    //subSquence += c1;
allCommonSubLen[i][j] = allCommonSubLen[i-1][j-1] + 1;
//System.out.println("i="+i+" ; j="+j+" ; subSquence="+subSquence);

                } else {
allCommonSubLen[i][j] = Math.max(allCommonSubLen[i-1][j], allCommonSubLen[i][j-1]);
if (allCommonSubLen[i][j] == allCommonSubLen[i-1][j]) {

                        //subSquence += c2;

                        //System.out.println("i="+i+" ; j="+j+" ; subSquence="+subSquence);

                    } else {

                        //subSquence += c1;

                        //System.out.println("i="+i+" ; j="+j+" ; subSquence="+subSquence);

                    }

                }

            }

        }

        //System.out.println(allCommonSubLen[len1][len2]);

    }