There are N cards placed face down in a row. On each card, an integer 1 or 2 is written.

Let A_i be the integer written on the i-th card.

Your objective is to guess A_1, A_2, ..., A_N correctly.

You know the following facts:

* For each i = 1, 2, ..., M, the value A_{X_i} + A_{Y_i} + Z_i is an even number.



You are a magician and can use the following magic any number of times:

Magic: Choose one card and know the integer A_i written on it. The cost of using this magic is 1.

What is the minimum cost required to determine all of A_1, A_2, ..., A_N?

It is guaranteed that there is no contradiction in given input.

Constraints

* All values in input are integers.
* 2 \leq N \leq 10^5
* 1 \leq M \leq 10^5
* 1 \leq X_i < Y_i \leq N
* 1 \leq Z_i \leq 100
* The pairs (X_i, Y_i) are distinct.
* There is no contradiction in input. (That is, there exist integers A_1, A_2, ..., A_N that satisfy the conditions.)

Input

Input is given from Standard Input in the following format:


N M
X_1 Y_1 Z_1
X_2 Y_2 Z_2
\vdots
X_M Y_M Z_M


Output

Print the minimum total cost required to determine all of A_1, A_2, ..., A_N.

Examples

Input

3 1
1 2 1


Output

2


Input

6 5
1 2 1
2 3 2
1 3 3
4 5 4
5 6 5


Output

2


Input

100000 1
1 100000 100


Output

99999
import java.io.BufferedReader;
import java.io.Closeable;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Map.Entry;
import java.util.StringTokenizer;

public class Main {
	
	public static boolean dfs(int node, int parent, ArrayList<HashSet<Integer>> adj, boolean[] visited, boolean[] looped) {
		if(looped[node]) { 
			return looped[node];
		}else if(visited[node]) {
			return looped[node] = true;
		}
		
		visited[node] = true;
		for(final int next : adj.get(node)) {
			if(next == parent) { continue; }
			
			if(dfs(next, node, adj, visited, looped)) {
				looped[node] = true;
			}
		}
		
		return looped[node];
	}
	
	public static void main(String[] args) throws IOException {
		try(final Scanner sc = new Scanner(System.in)){
			final int N = sc.nextInt();
			final int M = sc.nextInt();
			
			ArrayList<HashSet<Integer>> adj = new ArrayList<HashSet<Integer>>();
			for(int i = 0; i < N; i++) { adj.add(new HashSet<Integer>()); }
			
			for(int i = 0; i < M; i++) {
				final int x = sc.nextInt() - 1;
				final int y = sc.nextInt() - 1;
				final int w = sc.nextInt();
				
				adj.get(x).add(y);
				adj.get(y).add(x);
			}
			
			boolean[] visited = new boolean[N];
			boolean[] looped = new boolean[N];
			
			
			int count = 0;
			for(int i = 0; i < N; i++) {
				if(visited[i]) { continue; }
				//System.out.println(i);
				
				if(dfs(i, -1, adj, visited, looped)) {
					//count += 1;
				}
				count += 1;
			}
			
			System.out.println(count);
		}
	}

	public static class Scanner implements Closeable {
		private BufferedReader br;
		private StringTokenizer tok;

		public Scanner(InputStream is) throws IOException {
			br = new BufferedReader(new InputStreamReader(is));
		}

		private void getLine() throws IOException {
			while(!hasNext()){
				tok = new StringTokenizer(br.readLine());
			}
		}

		private boolean hasNext() {
			return tok != null && tok.hasMoreTokens();
		}

		public String next() throws IOException {
			getLine();
			return tok.nextToken();
		}

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

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

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

		public int[] nextIntArray(int n) throws IOException {
			final int[] ret = new int[n];
			for(int i = 0; i < n; i++){
				ret[i] = this.nextInt();
			}
			return ret;
		}

		public long[] nextLongArray(int n) throws IOException {
			final long[] ret = new long[n];
			for(int i = 0; i < n; i++){
				ret[i] = this.nextLong();
			}
			return ret;
		}

		public void close() throws IOException {
			br.close();
		}
	}
}