Java Utililty Methods Array Common Prefix

if (strs == null || strs.length == 0) {
    return "";
int minLen = Integer.MAX_VALUE;
for (String str : strs) {
    minLen = Math.min(minLen, str.length());
int low = 1;
...

if (str1 == null || str2 == null || str1.length() == 0 || str2.length() == 0) {
    return 0;
char[] cs1 = str1.toCharArray(), cs2 = str2.toCharArray();
int[][] longest = new int[str1.length() + 1][str2.length() + 1];
for (int i = 0; i <= str1.length(); i++) {
    longest[i][0] = 0;
for (int i = 0; i <= str2.length(); i++) {
    longest[0][i] = 0;
for (int i = 1; i <= str1.length(); i++) {
    for (int j = 1; j <= str2.length(); j++) {
        int max = Integer.max(longest[i - 1][j], longest[i][j - 1]);
        if (cs1[i - 1] == cs2[j - 1]) {
            max = Integer.max(longest[i - 1][j - 1] + 1, max);
        longest[i][j] = max;
return longest[str1.length()][str2.length()];

if (s1.isEmpty() || s2.isEmpty()) {
    return 0;
int m = s1.length();
int n = s2.length();
int cost = 0;
int maxLen = 0;
int[] p = new int[n];
...

StringBuilder sb = new StringBuilder();
if (null == firstString || null == secondString) {
    return "";
int[][] num = new int[firstString.length()][secondString.length()];
int maxlen = 0;
int lastSubsBegin = 0;
for (int i = 0; i < firstString.length(); i++) {
...

int Start = 0;
int Max = 0;
for (int i = 0; i < S1.length(); i++) {
    for (int j = 0; j < S2.length(); j++) {
        int x = 0;
        while (S1.charAt(i + x) == S2.charAt(j + x)) {
            x++;
            if (((i + x) >= S1.length()) || ((j + x) >= S2.length()))
...

if (seq1 == null)
    throw new IllegalArgumentException("seq1 is null");
if (seq2 == null)
    throw new IllegalArgumentException("seq2 is null");
if (maxLength < 0)
    throw new IllegalArgumentException("maxLength < 0 " + maxLength);
final int end = Math.min(seq1.length, Math.min(seq2.length, maxLength));
for (int i = 0; i < end; i++) {
...