A = input() B = input() m = len(A) n = len(B) dp = [[1 for j in range(n + 1)] for i in range(m + 1)] for i in range(m + 1): # 第0列 dp[i][0] = i for j in range(n + 1): # 第0行 dp[0][j] = j for i in range(1, m + 1): for j in range(1, n + 1): if A[i - 1] == B[j - 1]: dp[i][j] = dp[i - 1][j - 1] else: dp[i][j] = min(dp[i - 1][j - 1] + 1, dp[i - 1][j] + 1, dp[i][j - 1] + 1) print(dp[m][n])