392. Is Subsequence

Easy
Given two strings s and t, return true if s is a subsequence of t, or false otherwise.
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: Suppose 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?
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解題

Runtime: 0 ms, faster than 100.00%
Memory Usage: 1.9 MB, less than 80.92%
func isSubsequence(s string, t string) bool {
if len(s)==0 { return true }
for i := 0; i < len(t); i++ {
if t[i] == s[0] { s = s[1:] }
if len(s)==0 { return true }
}
return false
}