Problem:
Score : 300 points

Problem Statement

Takahashi has N balls. Initially, an integer A_i is written on the i-th ball.

He would like to rewrite the integer on some balls so that there are at most K different integers written on the N balls.

Find the minimum number of balls that Takahashi needs to rewrite the integers on them.

Constraints

1 \leq K \leq N \leq 200000

1 \leq A_i \leq N

All input values are integers.

Input

Input is given from Standard Input in the following format:

N K
A_1 A_2 ... A_N

Output

Print the minimum number of balls that Takahashi needs to rewrite the integers on them.

Sample Input 1

5 2
1 1 2 2 5

Sample Output 1

1

For example, if we rewrite the integer on the fifth ball to 2, there are two different integers written on the balls: 1 and 2.
On the other hand, it is not possible to rewrite the integers on zero balls so that there are at most two different integers written on the balls, so we should print 1.

Sample Input 2

4 4
1 1 2 2

Sample Output 2

0

Already in the beginning, there are two different integers written on the balls, so we do not need to rewrite anything.

Sample Input 3

10 3
5 1 3 2 4 1 1 2 3 4

Sample Output 3

3

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.StringTokenizer;


public class Main
{
	public static void main( String[] args ) throws IOException
	{
		Reader.init(System.in);
		int n = Reader.nextInt();
		int k = Reader.nextInt();
		int[] arey = new int[n];
		for ( int i2 = 0 ; i2 < n ; i2++ )
		{
			arey[i2] = Reader.nextInt();
		}
		Arrays.sort(arey);
		HashMap<Integer,Integer> map = new HashMap<Integer,Integer>();
		for ( int i = 0 ; i < n ; i++ )
		{
			if ( map.containsKey(arey[i]) )
			{
				map.put(arey[i], map.get(arey[i])+1);
			}
			else
			{
				map.put(arey[i],1);
			}
		}

        Map<Integer, Integer> result2 = new LinkedHashMap<>();
        map.entrySet().stream()
                .sorted(Map.Entry.<Integer, Integer>comparingByValue())
                .forEachOrdered(x -> result2.put(x.getKey(), x.getValue()));

/*        for ( Entry<Integer, Integer> entry : result2.entrySet())
        {
        	Integer key = entry.getKey();
            Integer value = (Integer) entry.getValue();
            System.out.println(key+"  "+value);
        }*/

        int size = result2.size();
        if ( size <= k )
        {
        	System.out.println("0");
        }
        else
        {
        	int actual = size - k;
	        int count = 0;
	        int k2 = 0;
	        for ( Entry<Integer, Integer> entry : result2.entrySet())
	        {
	            Integer value = (Integer) entry.getValue();
	            count = count + value;
	            k2++;
	            if ( k2 == actual )
	            {
	            	break;
	            }
	        }
	        System.out.println(count);
        }
	}
}

/** Class for buffered reading int and double values */
class Reader
{
    static BufferedReader reader;
    static StringTokenizer tokenizer;

    /** call this method to initialize reader for InputStream */
    static void init(InputStream input)
    {
        reader = new BufferedReader(new InputStreamReader(input) );
        tokenizer = new StringTokenizer("");
    }
    /** get next word */
    static String next() throws IOException {
        while ( ! tokenizer.hasMoreTokens() )
        {
            //TODO add check for eof if necessary
            tokenizer = new StringTokenizer(
                   reader.readLine() );
        }
        return tokenizer.nextToken();
    }

    static int nextInt() throws IOException {
        return Integer.parseInt( next() );
    }

    static double nextDouble() throws IOException {
        return Double.parseDouble( next() );
    }

    static long nextLong() throws IOException {
        return Long.parseLong( next() );
    }
}