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Introduction To Java
JAVA was developed by James Gosling at Sun Microsystems Inc in the year 1991, later acquired by Oracle Corporation. It is a simple programming language. Java makes writing, compiling, and debugging programming easy. It helps to create reusable code and modular programs.
Java is a class-based, object-oriented programming language and is designed to have as few implementation dependencies as possible. A general-purpose programming language made for developers to write once run anywhere that is compiled Java code can run on all platforms that support Java. Java applications are compiled to byte code that can run on any Java Virtual Machine. The syntax of Java is similar to c/c++.
Link for the Problem – Java Arraylist – Hacker Rank Solution
Java Arraylist – Hacker Rank Solution
Problem :
Sometimes it’s better to use dynamic size arrays. Java’s Arraylist can provide you this feature. Try to solve this problem using Arraylist.
You are given lines. In each line there are zero or more integers. You need to answer a few queries where you need to tell the number located in position of line.
Take your input from System.in.
Input Format
The first line has an integer . In each of the next lines there will be an integer denoting number of integers on that line and then there will be space-separated integers. In the next line there will be an integer denoting number of queries. Each query will consist of two integers and .
Constraints
Each number will fit in signed integer.
Total number of integers in lines will not cross .
Output Format
In each line, output the number located in position of line. If there is no such position, just print “ERROR!”
Sample Input
5 5 41 77 74 22 44 1 12 4 37 34 36 52 0 3 20 22 33 5 1 3 3 4 3 1 4 3 5 5
Sample Output
74 52 37 ERROR! ERROR!
Explanation
The diagram below explains the queries:

Java Arraylist – Hacker Rank Solution
import java.util.ArrayList; import java.util.List; import java.util.Scanner; public class Solution { public static void main(String[] args) { Scanner in = new Scanner(System.in); List<List<Integer>> lines = new ArrayList<List<Integer>>(); int n = in.nextInt(); for (int i = 0; i < n; i++) { List<Integer> line = new ArrayList<Integer>(); int d = in.nextInt(); for (int j = 0; j < d; j++) { line.add(in.nextInt()); } lines.add(line); } int q = in.nextInt(); for (int i = 0; i < q; i++) { int x = in.nextInt(); int y = in.nextInt(); if (y > lines.get(x - 1).size()) { System.out.println("ERROR!"); } else { System.out.println(lines.get(x - 1).get(y - 1)); } } in.close(); } }
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