再编辑距离(一)的基础上增加了权值

#
# 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可
#
# min edit cost
# @param str1 string字符串 the string
# @param str2 string字符串 the string
# @param ic int整型 insert cost
# @param dc int整型 delete cost
# @param rc int整型 replace cost
# @return int整型
#
class Solution:
    def minEditCost(self , str1: str, str2: str, ic: int, dc: int, rc: int) -> int:
        # write code here
        m, n = len(str1), len(str2)
        dp = [[0]*(n+1) for _ in range(m+1)]
        for i in range(m+1):
            for j in range(n+1):
                if i==0 and j==0:#处理原点
                    dp[i][j] = 0
                elif i==0:#处理第0行
                    dp[i][j] = dp[i][j-1]+ic
                elif j==0:#处理第0列
                    dp[i][j] = dp[i-1][j]+dc
                elif str1[i-1]==str2[j-1]:#相等时
                    dp[i][j] = dp[i-1][j-1]
                else:#不相等时,插入、删除、替换
                    dp[i][j] = min(dp[i][j-1]+ic,dp[i-1][j]+dc,dp[i-1][j-1]+rc)
        return dp[-1][-1]