Problem

Given a string s and a string t, check if s is subsequence of t.

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).

Follow up: If there are lots of incoming S, say S1, S2, … , Sk where k >= 1B, and you want to check one by one to see if T has its subsequence. In this scenario, how would you change your code?

example 1

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

example 2

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

Constraints

• 0 <= len(s) <= 100
• 0 <= len(t) <= 10^4
• Both strings consists only of lowercase characters.

Solution

Walking throw strings

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func isSubsequence(s string, t string) bool {
    isx, itx :=0, 0

    for isx<len(s) && itx<len(t) {
        if s[isx] == t[itx] {
            isx++
        }  
        itx++
    }
    return isx == len(s)
}