Problem

Given two strings s1 and s2, find the length of the longest common subsequence.

A subsequence is derived by deleting some or no characters from the string without altering the order of the remaining characters.

Return 0 if no common subsequence exists.

Examples

findLCSLength("abcdefg", "bdg")
// return 3
// Why? The LCS is "bdg"

findLCSLength("aggtab", "gxtxayb")
// return 4
// Why? The LCS is "gtab"