Print first K distinct Moran numbers from a given array

Given an array arr[] consisting of N distinct positive integers, the task is to print the first K distinct Moran Numbers from the given array.

A number N is a Moran number if N divided by the sum of its digits gives a prime number. 
Examples: 18, 21, 27, 42, 45

Examples:

Input: arr[] = {192, 21, 18, 138, 27, 42, 45}, K = 4 
Output: 21, 27, 42, 45 
Explanation:

• The sum of digits of the integer 21 is 2 + 1 = 3. Therefore, dividing 21 by its sum of digits = 21 / 3 = 7, which is a prime number.
• The sum of digits of the integer 27 is 2 + 7 = 9. Therefore, dividing 27 by its sum of digits results in 27 / 9 = 3, which is a prime number.
• The sum of digits of the integer 42 is 4 + 2 = 6. Therefore, dividing 42 by its sum of digits results in 42 / 6 = 7, which is a prime number.
• The sum of digits of the integer 45 is 4 + 5 = 9. Therefore, dividing 45 by its sum of digits results in 45 / 9 = 5, which is a prime number.

Input: arr[]={127, 186, 198, 63, 27, 91}, K = 3 
Output: 27, 63, 198

Approach: Follow the steps given below to solve the problem:

1. Sort the array
2. Traverse the sorted array and for each element, check if it is a Moran number or not
3. If found to be true, insert the element in a Set and increment the counter until it reaches K.
4. Print the elements in the Set when the size of the set is equal to K.

Below is the implementation of the above approach:

C++

#include <algorithm>
#include <iostream>
#include <set>
using namespace std;

// Function to calculate the
// sum of digits of a number
int digiSum(int a)
{
    // Stores the sum of digits
    int sum = 0;
    while (a) {

        // Add the digit to sum
        sum += a % 10;

        // Remove digit
        a = a / 10;
    }

    // Returns the sum
    // of digits
    return sum;
}

// Function to check if a number
// is prime or not
bool isPrime(int r)
{
    bool s = true;

    for (int i = 2; i * i <= r; i++) {

        // If r has any divisor
        if (r % i == 0) {

            // Set r as non-prime
            s = false;
            break;
        }
    }
    return s;
}

// Function to check if a
// number is moran number
bool isMorannumber(int n)
{
    int dup = n;

    // Calculate sum of digits
    int sum = digiSum(dup);

    // Check if n is divisible
    // by the sum of digits
    if (n % sum == 0) {

        // Calculate the quotient
        int c = n / sum;

        // If the quotient is prime
        if (isPrime(c)) {

            return true;
        }
    }

    return false;
}

// Function to print the first K
// Moran numbers from the array
void FirstKMorannumber(int a[],
                       int n, int k)
{
    int X = k;

    // Sort the given array
    sort(a, a + n);

    // Initialise a set
    set<int> s;

    // Traverse the array from the end
    for (int i = n - 1; i >= 0
                        && k > 0;
         i--) {
        // If the current array element
        // is a Moran number
        if (isMorannumber(a[i])) {

            // Insert into the set
            s.insert(a[i]);
            k--;
        }
    }

    if (k > 0) {
        cout << X << " Moran numbers are"
             << " not present in the array" << endl;
        return;
    }

    set<int>::iterator it;
    for (it = s.begin(); it != s.end(); ++it) {
        cout << *it << ", ";
    }
    cout << endl;
}

// Driver Code
int main()
{

    int A[] = { 34, 198, 21, 42,
                63, 45, 22, 44, 43 };
    int K = 4;

    int N = sizeof(A) / sizeof(A[0]);

    FirstKMorannumber(A, N, K);

    return 0;
}

Java

import java.io.*;
import java.util.*;

class GFG{

// Function to calculate the
// sum of digits of a number
static int digiSum(int a)
{

    // Stores the sum of digits
    int sum = 0;
    while (a != 0)
    {

        // Add the digit to sum
        sum += a % 10;

        // Remove digit
        a = a / 10;
    }

    // Returns the sum
    // of digits
    return sum;
}

// Function to check if a number
// is prime or not
static boolean isPrime(int r)
{
    boolean s = true;

    for(int i = 2; i * i <= r; i++)
    {

        // If r has any divisor
        if (r % i == 0)
        {

            // Set r as non-prime
            s = false;
            break;
        }
    }
    return s;
}

// Function to check if a
// number is moran number
static boolean isMorannumber(int n)
{
    int dup = n;

    // Calculate sum of digits
    int sum = digiSum(dup);

    // Check if n is divisible
    // by the sum of digits
    if (n % sum == 0)
    {

        // Calculate the quotient
        int c = n / sum;

        // If the quotient is prime
        if (isPrime(c))
        {
            return true;
        }
    }
    return false;
}

// Function to print the first K
// Moran numbers from the array
static void FirstKMorannumber(int[] a,
                              int n, int k)
{
    int X = k;

    // Sort the given array
    Arrays.sort(a);

    // Initialise a set
    TreeSet<Integer> s = new TreeSet<Integer>();

    // Traverse the array from the end
    for(int i = n - 1; i >= 0 && k > 0; i--)
    {

        // If the current array element
        // is a Moran number
        if (isMorannumber(a[i]))
        {

            // Insert into the set
            s.add(a[i]);
            k--;
        }
    }

    if (k > 0)
    {
        System.out.println(X + " Moran numbers are" +
                               " not present in the array");
        return;
    }

    for(int value : s)
        System.out.print(value + ", ");

    System.out.print("\n");
}

// Driver Code
public static void main(String[] args)
{
    int[] A = { 34, 198, 21, 42,
                63, 45, 22, 44, 43 };
    int K = 4;

    int N = A.length;

    FirstKMorannumber(A, N, K);
}
}

// This code is contributed by akhilsaini

Python3

import math

# Function to calculate the
# sum of digits of a number
def digiSum(a):

    # Stores the sum of digits
    sums = 0
    while (a != 0):

        # Add the digit to sum
        sums += a % 10

        # Remove digit
        a = a // 10

    # Returns the sum
    # of digits
    return sums

# Function to check if a number
# is prime or not
def isPrime(r):

    s = True

    for i in range(2, int(math.sqrt(r)) + 1):

        # If r has any divisor
        if (r % i == 0):

            # Set r as non-prime
            s = False
            break

    return s

# Function to check if a
# number is moran number
def isMorannumber(n):

    dup = n

    # Calculate sum of digits
    sums = digiSum(dup)

    # Check if n is divisible
    # by the sum of digits
    if (n % sums == 0):

        # Calculate the quotient
        c = n // sums

        # If the quotient is prime
        if isPrime(c):
            return True

    return False

# Function to print the first K
# Moran numbers from the array
def FirstKMorannumber(a, n, k):

    X = k

    # Sort the given array
    a.sort()

    # Initialise a set
    s = set()

    # Traverse the array from the end
    for i in range(n - 1, -1, -1):
        if (k <= 0):
            break

        # If the current array element
        # is a Moran number
        if (isMorannumber(a[i])):

            # Insert into the set
            s.add(a[i])
            k -= 1

    if (k > 0):
        print(X, end =' Moran numbers are not '
                       'present in the array')
        return

    lists = sorted(s)
    for i in lists:
        print(i, end = ', ')

# Driver Code
if __name__ == '__main__':

    A = [ 34, 198, 21, 42,
          63, 45, 22, 44, 43 ]
    K = 4

    N = len(A)

    FirstKMorannumber(A, N, K)

# This code is contributed by akhilsaini

C#

using System;
using System.Collections;
using System.Collections.Generic;

class GFG{

// Function to calculate the
// sum of digits of a number
static int digiSum(int a)
{

    // Stores the sum of digits
    int sum = 0;
    while (a != 0)
    {

        // Add the digit to sum
        sum += a % 10;

        // Remove digit
        a = a / 10;
    }

    // Returns the sum
    // of digits
    return sum;
}

// Function to check if a number
// is prime or not
static bool isPrime(int r)
{
    bool s = true;

    for(int i = 2; i * i <= r; i++)
    {

        // If r has any divisor
        if (r % i == 0)
        {

            // Set r as non-prime
            s = false;
            break;
        }
    }
    return s;
}

// Function to check if a
// number is moran number
static bool isMorannumber(int n)
{
    int dup = n;

    // Calculate sum of digits
    int sum = digiSum(dup);

    // Check if n is divisible
    // by the sum of digits
    if (n % sum == 0)
    {

        // Calculate the quotient
        int c = n / sum;

        // If the quotient is prime
        if (isPrime(c))
        {
            return true;
        }
    }
    return false;
}

// Function to print the first K
// Moran numbers from the array
static void FirstKMorannumber(int[] a,
                              int n, int k)
{
    int X = k;

    // Sort the given array
    Array.Sort(a);

    // Initialise a set
    SortedSet<int> s = new SortedSet<int>();

    // Traverse the array from the end
    for(int i = n - 1; i >= 0 && k > 0; i--)
    {

        // If the current array element
        // is a Moran number
        if (isMorannumber(a[i]))
        {

            // Insert into the set
            s.Add(a[i]);
            k--;
        }
    }

    if (k > 0)
    {
        Console.WriteLine(X + " Moran numbers are" +
                              " not present in the array");
        return;
    }

    foreach(var val in s)
    {
        Console.Write(val + ", ");
    }
    Console.Write("\n");
}

// Driver Code
public static void Main()
{
    int[] A = { 34, 198, 21, 42,
                63, 45, 22, 44, 43 };
    int K = 4;

    int N = A.Length;

    FirstKMorannumber(A, N, K);
}
}

// This code is contributed by akhilsaini

Javascript

<script>

// Function to calculate the
// sum of digits of a number
function digiSum(a)
{
    // Stores the sum of digits
    let sum = 0;
    while (a) {

        // Add the digit to sum
        sum += a % 10;

        // Remove digit
        a = Math.floor(a / 10);
    }

    // Returns the sum
    // of digits
    return sum;
}

// Function to check if a number
// is prime or not
function isPrime(r)
{
    let s = true;

    for (let i = 2; i * i <= r; i++) {

        // If r has any divisor
        if (r % i == 0) {

            // Set r as non-prime
            s = false;
            break;
        }
    }
    return s;
}

// Function to check if a
// number is moran number
function isMorannumber(n)
{
    let dup = n;

    // Calculate sum of digits
    let sum = digiSum(dup);

    // Check if n is divisible
    // by the sum of digits
    if (n % sum == 0) {

        // Calculate the quotient
        let c = n / sum;

        // If the quotient is prime
        if (isPrime(c)) {

            return true;
        }
    }

    return false;
}

// Function to print the first K
// Moran numbers from the array
function FirstKMorannumber(a, n, k)
{
    let X = k;

    // Sort the given array
    a = a.sort((x, y) => x - y)

    // Initialise a set
    let s = new Set();

    // Traverse the array from the end
    for (let i = n - 1; i >= 0
                        && k > 0;
         i--) {
        // If the current array element
        // is a Moran number
        if (isMorannumber(a[i])) {

            // Insert into the set
            s.add(a[i]);
            k--;
        }
    }

    if (k > 0) {
        document.write(X + " Moran numbers are"
             + " not present in the array"  + "<br>");
        return;
    }

    // Convert the set into array and then sort the array

    s = [...s].sort((a, b) => a - b)

    for (let it of s) {
        document.write(it + ", ");
    }
    document.write("<br>");
}

// Driver Code

    let A = [ 34, 198, 21, 42,
                63, 45, 22, 44, 43 ];
    let K = 4;

    let N = A.length;

    FirstKMorannumber(A, N, K);

    // This code is contributed by gfgking

</script>

Output:

42, 45, 63, 198,

Time Complexity: O(N^3/2)
Auxiliary Space: O(N)