To some string S, we will perform some replacement operations that replace groups of letters with new ones (not necessarily the same size).
Each replacement operation has 3 parameters: a starting index i, a source word x and a target word y.  The rule is that if x starts at position i in the original string S, then we will replace that occurrence of x with y.  If not, we do nothing.
For example, if we have S = "abcd" and we have some replacement operation i = 2, x = "cd", y = "ffff", then because "cd" starts at position 2 in the original string S, we will replace it with "ffff".
Using another example on S = "abcd", if we have both the replacement operation i = 0, x = "ab", y = "eee", as well as another replacement operation i = 2, x = "ec", y = "ffff", this second operation does nothing because in the original string S[2] = 'c', which doesn't match x[0] = 'e'.
All these operations occur simultaneously.  It's guaranteed that there won't be any overlap in replacement: for example, S = "abc", indexes = [0, 1], sources = ["ab","bc"] is not a valid test case.
Example 1:
Input: S = "abcd", indexes = [0,2], sources = ["a","cd"], targets = ["eee","ffff"]
Output: "eeebffff"
Explanation: "a" starts at index 0 in S, so it's replaced by "eee".
"cd" starts at index 2 in S, so it's replaced by "ffff".
Example 2:
Input: S = "abcd", indexes = [0,2], sources = ["ab","ec"], targets = ["eee","ffff"]
Output: "eeecd"
Explanation: "ab" starts at index 0 in S, so it's replaced by "eee". 
"ec" doesn't starts at index 2 in the original S, so we do nothing.
Notes:
0 <= indexes.length = sources.length = targets.length <= 100
0 < indexes[i] < S.length <= 1000
All characters in given inputs are lowercase letters.
class Solution:
    def findReplaceString(self, S: str, indexes: List[int], sources: List[str], targets: List[str]) -> str:
        S = list(S)
        for i, s, t in sorted(zip(indexes,sources,targets),reverse=True):
            appl = all([(i + ind < len(S)) and (S[i+ind] == s[ind]) for ind in range(len(s))])
            if appl:
                S[i:i+len(s)] = list(t)
        return ''.join(S)
        

class Solution:
    def findReplaceString(self, S: str, indexes: List[int], sources: List[str], targets: List[str]) -> str:
        S = list(S)
        for i, s, t in sorted(zip(indexes,sources,targets),reverse=True):
            appl = all([(i + ind < len(S)) and (S[i+ind] == s[ind]) for ind in range(len(s))])
            if appl:
                S[i:i+len(s)] = list(t)
        return ''.join(S)
        
