Number_of_Matching_Subsequences.py

# Runtime = 1104ms (58.9%) 
# Memory = 16.9MB (90.44%)

class Solution(object):
    def numMatchingSubseq(self, s, words):
        def is_sub(word):
            index=-1
            for ch in word:
                index=s.find(ch,index+1)
                if index==-1:
                    return False
            return True
        c=0
        for word in words:
            if is_sub(word):
                c+=1
        return c