## Java Hashset HackerRank Solution

In computer science, a set is an abstract data type that can store certain values, without any particular order, and no repeated values(Wikipedia).{1,2,3} is an example of a set, but {1,2,2} is not a set. Today you will learn how to use sets in java by solving this problem.

You are given pairs of strings. Two pairs (a,b) and (c,d) are identical if a=c and b=d. That also implies (a,b) is *not* same as (b,a). After taking each pair as input, you need to print number of unique pairs you currently have.

Complete the code in the editor to solve this problem.

**Input Format**

In the first line, there will be an integer T denoting number of pairs. Each of the next T lines will contain two strings seperated by a single space.

**Constraints:**

- 1<=T<=100000
- Length of each string is atmost 5 and will consist lower case letters only.

**Output Format**

Print T lines. In the ith line, print number of unique pairs you have after taking ith pair as input.

**Sample Input**

5 john tom john mary john tom mary anna mary anna

**Sample Output**

1 2 2 3 3

**Explanation**

- After taking the first input, you have only one pair: (john,tom)
- After taking the second input, you have two pairs: (john, tom) and (john, mary)
- After taking the third input, you still have two unique pairs.
- After taking the fourth input, you have three unique pairs: (john,tom), (john, mary) and (mary, anna)
- After taking the fifth input, you still have three unique pairs.

Code Solution:

//Java Hashset HackerRank Solution import java.io.*; import java.util.*; import java.text.*; import java.math.*; import java.util.regex.*; public class Solution { public static void main(String[] args) { Scanner s = new Scanner(System.in); int t = s.nextInt(); String [] pair_left = new String[t]; String [] pair_right = new String[t]; for (int i = 0; i < t; i++) { pair_left[i] = s.next(); pair_right[i] = s.next(); } //Write your code here HashSet<String> pairs = new HashSet<String>(t); for(int i = 0; i < t; i++) { pairs.add("(" + pair_left[i] + ", " + pair_right[i] + ")" ); System.out.println(pairs.size()); } } } //Java Hashset HackerRank Solution

Disclaimer: This problem is originally created and published by HackerRank, we only provide solutions to this problem. Hence, doesn’t guarantee the truthfulness of the problem. This is only for information purposes.