To String contains compare O(n)

 Given two strings, determine if they share a common substring. A substring may be as small as one character.

For example, the words "a", "and", "art" share the common substring . The words "be" and "cat" do not share a substring.

Function Description

Complete the function twoStrings in the editor below. It should return a string, either YES or NO based on whether the strings share a common substring.

twoStrings has the following parameter(s):

• s1, s2: two strings to analyze .

Input Format

The first line contains a single integer , the number of test cases.

The following  pairs of lines are as follows:

• The first line contains string .
• The second line contains string .

Constraints:

•  and  consist of characters in the range ascii[a-z]                                            

Output Format

For each pair of strings, return YES or NO.

Sample Input

2
hello
world
hi
world

Sample Output

YES
NO

Explanation

We have  pairs to check:

1. , . The substrings  and  are common to both strings.
2. , .  and  share no common substrings.

Solutions:

import java.io.*;

import java.math.*;

import java.security.*;

import java.text.*;

import java.util.*;

import java.util.concurrent.*;

import java.util.regex.*;

public class Solution { 

    static String twoStrings(String s1, String s2) {

      Set<Character> a1 = new HashSet<>();

        Set<Character> a2 = new HashSet<>();

        for (int i = 0; i < s1.length(); i++) {

            a1.add(s1.charAt(i));

        }

        for (int i = 0; i < s2.length(); i++) {

            a2.add(s2.charAt(i));

        }

        for (char ch : a1) {

            if (a2.contains(ch)) {

                return "YES";

            } 

        }

        return "NO";

    }

    private static final Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) throws IOException {

        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));

        int q = scanner.nextInt();

        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

        for (int qItr = 0; qItr < q; qItr++) {

            String s1 = scanner.nextLine();

            String s2 = scanner.nextLine();

            String result = twoStrings(s1, s2);

            bufferedWriter.write(result);

            bufferedWriter.newLine();

        }

        bufferedWriter.close();

        scanner.close();

    }

}