a, b = ' ' + input(), ' ' + input() dp = [[''] * len(b) for _ in range(len(a))] for i in range(1, len(a)): for j in range(1, len(b)): if a[i] == b[j]: dp[i][j] = dp[i - 1][j - 1] + a[i] else: if len(dp[i - 1][j]) >= len(dp[i][j - 1]): dp[i][j] = dp[i - 1][j] else: dp[i][j] = dp[i][j - 1] print(len(dp[-1][-1])) print(dp[-1][-1]) dp, LCS