【leetcode】791. Custom Sort String

7.68%

class Solution(object):
    def customSortString(self, S, T):
        """
        :type S: str
        :type T: str
        :rtype: str
        """
        lists = []
        result = ''
        dicts = {}
        for i,s in enumerate(S):
            dicts[s] = i
        for char in T:
            if char in dicts.keys():
                lists.append([char,dicts[char]])
            else:
                result += char
        lists = sorted(lists,key = lambda x:x[1])
        for i in lists:
            result += i[0]
        return result 

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88.75%  很妙 直接用要求的顺序找char即可

class Solution(object):
    def customSortString(self, S, T):
        """
        :type S: str
        :type T: str
        :rtype: str
        """
        result = []
        for char in S:
            result.append(char*T.count(char))
        for char in T:
            if char not in S:
                result.append(char)    
        return ''.join(result)

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68.37% 主要学习一下字典的collections的Counter函数

from collections import Counter
class Solution(object):
    def customSortString(self, S, T):
        """
        :type S: str
        :type T: str
        :rtype: str
        """
        result = ''
        counts = Counter(T)
        for char in S:
            result += char*counts[char]
            del counts[char]
        for char,cnt in counts.items():
            result += char*cnt
        return ''.join(result)

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78.62%  又一个很巧妙的，主要是熟练运用sorted函数，而且不仅仅是list可以使用，string也是一个迭代器所以也是可以用。

注意sorted返回的是一个排好序的list，所以可以用join函数相连。

from collections import Counter
class Solution(object):
    def customSortString(self, S, T):
        """
        :type S: str
        :type T: str
        :rtype: str
        """
        return ''.join(sorted(T,key= lambda x:S.index(x) if x in S else 26))

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59.8%  又一个抖机灵是可以直接把已经筛选过的字符换成空字符，就不用再循环一遍看看还有啥没有筛选过

from collections import Counter
class Solution(object):
    def customSortString(self, S, T):
        """
        :type S: str
        :type T: str
        :rtype: str
        """
        result = ''
        for char in S:
            result += char*T.count(char)
            T = T.replace(char,'')
        return result+T