HackerRank Problem #21

Between Two Sets

Problem

There will be two arrays of integers. Determine all integers that satisfy the following two conditions:

1. The elements of the first array are all factors of the integer being considered
2. The integer being considered is a factor of all elements of the second array

These numbers are referred to as being between the two arrays. Determine how many such numbers exist.

Example

a = [2, 6]

b = [24, 36]

There are two numbers between the arrays: 6 and 12. 6%2 = 0, 6%6 = 0, 24%6 = 0 and 36%6 = 0 for the first value. 12%2 = 0, 12%6 = 0 and 24%12 = 0, 36%12 = 0 for the second value. Return 2.

Function Description

Complete the getTotalX function in the editor below. It should return the number of integers that are between the sets.

getTotalX has the following parameter(s):

• int a[n]: an array of integers
• int b[m]: an array of integers

Returns

• int: the number of integers that are between the sets

Input Format

The first line contains two space-separated integers, n and m, the number of elements in arrays a and b. The second line contains n distinct space-separated integers a[i] where 0 ≤ i < n. The third line contains distinct space-separated integers b[j] where 0 ≤ j < m.

Constraints

• 1 ≤ n, m ≤ 10
• 1 ≤ a[i] ≤ 100
• 1 ≤ b[j] ≤ 100

Sample Input

2 3
2 4
16 32 96

Sample Output

3

Explanation

2 and 4 divide evenly into 4, 8, 12 and 16. 4, 8 and 16 divide evenly into 16, 32, 96.

4, 8 and 16 are the only three numbers for which each element of a is a factor and each is a factor of all elements of b.

Solution

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.function.*;
import java.util.regex.*;
import java.util.stream.*;
import static java.util.stream.Collectors.joining;
import static java.util.stream.Collectors.toList;

class Result {

    /*
     * Complete the 'getTotalX' function below.
     *
     * The function is expected to return an INTEGER.
     * The function accepts following parameters:
     *  1. INTEGER_ARRAY a
     *  2. INTEGER_ARRAY b
     */

    public static int getTotalX(List<Integer> a, List<Integer> b) {
    // Write your code here
        int lastIndexOfA = a.size()-1;
        int firstFactor = 0;
        for(int i=0; i<a.size(); i++){
            if(a.get(lastIndexOfA) % a.get(i)==0){
                firstFactor = a.get(lastIndexOfA);
            } else{
                firstFactor = a.get(lastIndexOfA)*(i+2);
            }
        }

        int result = 0;
        for(int j=1; j*firstFactor <= b.get(0); j++){
            boolean isFactor = true;
            int factor = j*firstFactor; 
            for(int i=0; i<a.size();i++){
                if(factor%a.get(i)!=0){
                    isFactor = false;
                }
            }
            for(int i=0; i<b.size();i++){
                if(b.get(i)%factor!=0){
                    isFactor = false;
                }
            }
            if(isFactor == true){
                result++;
            }
        }
        return result;
    }

}

public class Solution {
    public static void main(String[] args) throws IOException {
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));

        String[] firstMultipleInput = bufferedReader.readLine().replaceAll("\\s+$", "").split(" ");

        int n = Integer.parseInt(firstMultipleInput[0]);

        int m = Integer.parseInt(firstMultipleInput[1]);

        List<Integer> arr = Stream.of(bufferedReader.readLine().replaceAll("\\s+$", "").split(" "))
            .map(Integer::parseInt)
            .collect(toList());

        List<Integer> brr = Stream.of(bufferedReader.readLine().replaceAll("\\s+$", "").split(" "))
            .map(Integer::parseInt)
            .collect(toList());

        int total = Result.getTotalX(arr, brr);

        bufferedWriter.write(String.valueOf(total));
        bufferedWriter.newLine();

        bufferedReader.close();
        bufferedWriter.close();
    }
}