LeetCode: 521. Longest Uncommon Subsequence I

LeetCode: 521. Longest Uncommon Subsequence I

Given a group of two strings, you need to find the longest uncommon
subsequence of this group of two strings. The longest uncommon
subsequence is defined as the longest subsequence of one of these
strings and this subsequence should not be any subsequence of the
other strings.

A subsequence is a sequence that can be derived from one sequence by
deleting some characters without changing the order of the remaining
elements. Trivially, any string is a subsequence of itself and an
empty string is a subsequence of any string.

The input will be two strings, and the output needs to be the length
of the longest uncommon subsequence. If the longest uncommon
subsequence doesn’t exist, return -1.

Example 1: Input: “aba”, “cdc” Output: 3 Explanation: The longest
uncommon subsequence is “aba” (or “cdc”), because “aba” is a
subsequence of “aba”, but not a subsequence of any other strings in
the group of two strings. Note:

Both strings’ lengths will not exceed 100. Only letters from a ~ z
will appear in input strings.
自己的答案：

public class Solution {    public int findLUSlength(String a, String b) {        int aLength = a.length();        int bLength = b.length();        if (aLength > bLength) {            return aLength;        } else if (aLength <bLength) {            return bLength;        }        int result = -1;        LOOP: for (int i = aLength; i > 0; i--) {            for (int j = 0; j <= aLength - i; j++) {                if (!b.contains(a.substring(j, j + i))) {                    result = i;                    break LOOP;                }            }        }        return result;    }}

问题解答：
Solution

效率最高的解答：

public class Solution {    public int findLUSlength(String a, String b) {        // 边界处理        if(a==null||b==null){            return -1;        }        int lena = a.length();        int lenb = b.length();        if(a.equals(b)){            return -1;        }        return lena>lenb?lena:lenb;    }}