問題
A subsequence is formed by deleting zero or more elements while preserving the order of the remaining elements. Find the longest length shared by two arrays. Matching elements need not be adjacent. Return only the length, since several equally long subsequences may exist.
Implement longest_common_subsequence_length(first, second).
Input
first: The first sequence.
second: The second sequence.
Output
Return the maximum common subsequence length. If either array is empty, return 0.
制約
Each array has 0…1,000 integers between −1,000,000,000 and 1,000,000,000. Duplicates are allowed.
例
入力：
first = [1, 3, 2, 4]
second = [3, 1, 2, 4]
期待される出力：
expected = 3入力：
std::vector<long long> first = {1, 3, 2, 4};
std::vector<long long> second = {3, 1, 2, 4};
期待される出力：
long long expected = 3;入力：
long[] first = new long[] {1, 3, 2, 4};
long[] second = new long[] {3, 1, 2, 4};
期待される出力：
long expected = 3;解説
Both contain [1, 2, 4] in that order, after deleting one value. The original arrays differ, so a length-four match is impossible.
入力：
first = [1, 2]
second = [3, 4]
期待される出力：
expected = 0入力：
std::vector<long long> first = {1, 2};
std::vector<long long> second = {3, 4};
期待される出力：
long long expected = 0;入力：
long[] first = new long[] {1, 2};
long[] second = new long[] {3, 4};
期待される出力：
long expected = 0;解説
The arrays have no shared value, so their only common subsequence is empty.
参考資料
この課題はCodeUtility用に調整されています。上記の説明と制約に従ってください。