Qfyilyi

There are a number of genes in a chromosome and your bioinformatic friend wants to check if a particular chromosome has a series of genes or not.
The sequence in which genes occur is important. You want to help your friend in this matter.
He gives you n chromosomes and a series of genes he wants to check. Help him identify whether these genes are present in the
chromosome in the given order.

Because you are not a biology student, he’s made things easier for you. He represents genes by a letter, number or special character present in ASCII.
Spaces do NOT represent a gene.

Example

If the chromosome is abdfgc, and the genes he’s querying for is abc, these are present (in the correct order) in the chromosome (marked in bold).
a*b*dfg*c*. However if the query is bca, this is not present in the correct order in the chromosome.

Input

The first line of input consists of an integer n which is the number of test cases.

Each test case consists of two lines of input:

• The first line contains the chromosome


• The second line contains the gene you are querying for
  Output

The output for that chromosome-gene pair should be “YES” if the genes, taken in order, are contained in the chromosome and “NO” otherwise.
The output should have n lines containing YES/NO.

Constraints

1 <= n <= 10000



1 <= |chromosome| <100



1 <= |gene| < |chromosome|

Sample Input

4

12sd78f

sf

12345efd

1e3d

ijkfgds

jkf

1111456

116

Sample Output

YES

NO

YES

YES

Code

import java.io.BufferedReader;

import java.io.InputStreamReader;



public class solution {



private static String checkGem(String ch, String gem) {



    int prevIndex = 0;

    for(int n=0; n < gem.length(); n++) {

        if(ch.indexOf(gem.charAt(n), prevIndex)==-1) {

            return "NO";

        }

        else {

            prevIndex = ch.indexOf(gem.charAt(n), prevIndex);

        }

    }



    return "YES";

}

public static void main(String args) throws Exception {



    //Scanner sc = new Scanner(System.in);

    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

    String test = br.readLine();    



    int t = Integer.parseInt(test);



    for(int i=0; i<t; i++) {

        String ch = br.readLine();

        String gem = br.readLine();

        ch = ch.replaceAll("\s","");

        gem =  gem.replaceAll("\s","");

        String ans = checkGem(ch, gem);

        System.out.println(ans);

    }



    }

}

You have a bug in your code. You can try this test case:

1

a

aaaaa

This one should be "NO", but your code output is "YES".

The problem is that you need to advance prevIndex it should be:

prevIndex = ch.indexOf(gem.charAt(n), prevIndex) + 1;