# 392. Is Subsequence
#
# Given a string s and a string t, check if s is subsequence of t.
#
# You may assume that there is only lower case English letters in both s and t. t is potentially a very long (length ~= 500,000) string, and s is a short string (<=100).
#
# A subsequence of a string is a new string which is formed from the original string by deleting some (can be none) of the characters without disturbing the relative positions of the remaining characters. (ie, "ace" is a subsequence of "abcde" while "aec" is not).
#
# Example 1:
# s = "abc", t = "ahbgdc"
#
# Return true.
#
# Example 2:
# s = "axc", t = "ahbgdc"
#
# Return false.

class Solution:
    def isSubsequence(self, s: str, t: str) -> bool:
        if s=="":
            if len(t)>=0:
                return True
        counter=-1
        for i in range(len(s)):
            if s[i] not in t[counter+1:]:
                return False
            else:
                t=t[t.index(s[i])+1:]
        return True
