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# Is Subsequence – Coding program

Given two strings `s` and `t`, return `true` if `s` is a subsequence of `t`, or `false` otherwise.

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 `"<u>a</u>b<u>c</u>d<u>e</u>"` while `"aec"` is not).

Example 1:

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

Example 2:

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

## Solution:

`````` public bool IsSubsequence(string s, string t) {
if(s.Length == 0) return true;
int sLength=0,tLength=0;
while(t.Length>tLength){
if(s[sLength]==t[tLength]){
sLength++;
if(sLength==s.Length) return true;
}
tLength++;
}
return false;
}``````

Here we are trying to search the sequence of `string s` in `string t`. adding the default case if s length is equal to zero then return `true`.

### Steps:

1. Start both string searches from the zeroth index.
2. While loop with check, t greater than s.
3. if(s[sLength]==t[tLength]) then only increase count of `sLength`and every time increase the count of `tLength`.
4. if(sLength==s.Length) then return `true` or else return by default `false`.

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