Is Subsequence

by raviteja gunda

HTML

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

JavaScript

function isSubsequence(s: string, t: string): boolean {
    let j: number = 0;
    if(s === t) {
        return true;
    }
    if(s.length > t.length) {
        return false;
    }
    for(let i = 0; i <= t.length; i++) {
        if(s.charAt(j) === t.charAt(i)) {
            j++;
        }
        if(j === s.length) return true;
    }
    return false;
};

//top

function isSubsequence(s: string, t: string): boolean {
    let sIndex = 0;
    let tIndex = 0;
    if (s.length === 0) return true;
    while (tIndex < t.length) {
        if (s[sIndex] === t[tIndex]) {
            sIndex++;
        }
        tIndex ++;
        if (sIndex === s.length) return true;
    }

    return false;
};