+ Longest string edit distance palindromic

72. Edit Distance

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Given two words word1 and word2 , and calculates an word1 converted word2 minimum number of operations used.

You can perform the following three operations on one word:

1. Insert a character
2. To delete a character
3. Replace a character

Example 1:

输入: word1 = "horse", word2 = "ros"
输出: 3
解释: 
horse -> rorse (将 'h' 替换为 'r')
rorse -> rose (删除 'r')
rose -> ros (删除 'e')

def minDistance(word1, word2) -> int:
    n = len(word1)
    m = len(word2)
    dp = [[0] * (n2 + 1) for _ in range(n1 + 1)]

    # init boundaries
    for i in range(n + 1):
        d[i][0] = i
    for j in range(m + 1):
        d[0][j] = j
        
    for i in range(1, n + 1):
        for j in range(1, m + 1):
            if word1[i-1] == word2[j-1]:
                dp[i][j] = dp[i-1][j-1]
            else:
                dp[i][j] = min(dp[i][j-1], dp[i-1][j], dp[i-1][j-1] ) + 1
    #print(dp)      
    return dp[-1][-1]

409. The longest palindrome string

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Given a capital letter and lowercase letter string comprising, configured to find the longest by letters palindromic sequence.

In the construction process, please note case sensitive. Example, "Aa"not as a palindrome string.

Note:
assuming that the length of the string is not more than 1,010.

Example 1:

输入:
"abccccdd"

输出:
7

解释:
我们可以构造的最长的回文串是"dccaccd", 它的长度是 7。

def longestPalindrome(s) -> int:
    if not s:
        return 0
    from collections import Counter
    dic = Counter(s)
    ans=0
    for v in dic.values():
        ans += v//2*2
        if ans % 2 == 0 and v % 2 == 1:#变为奇数后，ans值不会在进行加一
            ans += 1
    return ans