
'''
Given two strings s and t, check if s is a subsequence of t.

A subsequence of a string is a new string that is formed from the original string by deleting some
(can be none) of the characters without disturbing the relative positions of the remaining characters.
(i.e., "ace" is a subsequence of "abcde" while "aec" is not).

 

Example 1:

Input: s = "abc", t = "ahbgdc"
Output: true

Example 2:

Input: s = "axc", t = "ahbgdc"
Output: false

 

Constraints:

    0 <= s.length <= 100
    0 <= t.length <= 104
    s and t consist only of lowercase English letters.

 
Follow up: If there are lots of incoming s, say s1, s2, ..., sk where k >= 109, and you want to check one by one
to see if t has its subsequence. In this scenario, how would you change your code?

'''

def isSubseq(s,t):
    i=0
    while i < len(s):
        increment = False
        for c in t:
            if s[i] == c:
                i += 1
                increment = True
        if not increment:
            return False
        
    if i==len(s):
        return True

    
print(isSubseq("abc","ahbgdc"))
print(isSubseq("axc","ahbgdc"))