class Solution:
  def findLCSLength(self, s1, s2):
    m = len(s1) + 1
    n = len(s2) + 1
    table = [[0] * n for _ in range(m)]
    
    for i in range(1, m):
      for j in range(1, n):
        if s1[i - 1] == s2[j - 1]:
          table[i][j] = table[i - 1][j - 1] + 1
        else:
          table[i][j] = max(table[i][j - 1],  table[i - 1][j])
        
    return table[-1][-1]