Algorithm
Problem Name: 521. Longest Uncommon Subsequence I
Given two strings a and b, return the length of the longest uncommon subsequence between a and b. If the longest uncommon subsequence does not exist, return -1.
An uncommon subsequence between two strings is a string that is a subsequence of one but not the other.
A subsequence of a string s is a string that can be obtained after deleting any number of characters from s.
- For example,
"abc"is a subsequence of"aebdc"because you can delete the underlined characters in"aebdc"to get"abc". Other subsequences of"aebdc"include"aebdc","aeb", and""(empty string).
Example 1:
Input: a = "aba", b = "cdc" Output: 3 Explanation: One longest uncommon subsequence is "aba" because "aba" is a subsequence of "aba" but not "cdc". Note that "cdc" is also a longest uncommon subsequence.
Example 2:
Input: a = "aaa", b = "bbb" Output: 3 Explanation: The longest uncommon subsequences are "aaa" and "bbb".
Example 3:
Input: a = "aaa", b = "aaa" Output: -1 Explanation: Every subsequence of string a is also a subsequence of string b. Similarly, every subsequence of string b is also a subsequence of string a.
Constraints:
1 <= a.length, b.length <= 100aandbconsist of lower-case English letters.
Code Examples
#1 Code Example with C Programming
Code -
C Programming
const findLUSlength = function(a, b) {
return a === b ? -1 : Math.max(a.length, b.length);
};
Input
a = "aba", b = "cdc"
Output
3
#2 Code Example with Python Programming
Code -
Python Programming
class Solution:
def findLUSlength(self, a, b):
"""
:type a: str
:type b: str
:rtype: int
"""
return -1 if a == b else max(len(a), len(b))
Input
a = "aba", b = "cdc"
Output
3
#3 Code Example with C# Programming
Code -
C# Programming
using System;
namespace LeetCode
{
public class _0521_LongestUncommonSubsequenceI
{
public int FindLUSlength(string a, string b)
{
if (a == b) return -1;
return Math.Max(a.Length, b.Length);
}
}
}
Input
a = "aaa", b = "bbb"
Output
3