Given two words word1 and word2, find the minimum number of steps required to convert word1 to word2. (each operation is counted as 1 step.)

You have the following 3 operations permitted on a word:

a) Insert a character

b) Delete a character

c) Replace a character

最短编辑距离，比较经典的DP求解问题

状态转移方程

dp[i][j] = min(dp[i - 1][j - 1] + same(word1[i - 1], word2[j - 1]), dp[i - 1][j] + 1, dp[i][j - 1] + 1)

初值

dp[0][j] = j

dp[i][0] = i

1 | class Solution { |