Longest Common Subsequence
Given two strings word1
and word2
, determine the length of the longest common subsequence between the two strings.
A subsequence consists of characters from the original string that appear in the same order but may not be consecutive. For instance, "ace" is a valid subsequence of "abcde", but "aec" is not. More formally, a subsequence of a string is derived by deleting zero or more characters from the original string, without altering the relative order of the remaining characters.
A common subsequence of two strings is a string that is a subsequence of both strings.
If the two strings share no common subsequences, the answer is 0
.
Example 1:
Input:
1word1 = "abcde" 2word2 = "ace"
Output: 3
Explanation:
The longest common subsequence is ace
and its length is 3
.
Example 2:
Input:
1word1 = "almost" 2word2 = "algomonster"
Output: 6
Explanation:
The longest common subsequence is almost
and its length is 6
.
Example 3:
Input:
1word1 = "abc" 2word2 = "def"
Output: 0
Explanation:
There is no such common subsequence, so the result is 0
.