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.util.Scanner;

public class Main {
	private static class UnionFind {
		int n;
		int[] p;
		int size;

		UnionFind(int n) {
			this.n = n;
			this.size = n;
			p = new int[n];
			for (int i = 0; i < n; i++) {
				p[i] = i;
			}
		}

		public void connect(int v, int u) {
			int rv = root(v);
			int ru = root(u);
			if (rv != ru) size--;
			p[rv] = p[ru];
		}

		public int size() {
			return size;
		}

		private int root(int v) {
			while (v != p[v]) {
				p[v] = p[p[v]];
				v = p[v];
			}
			return p[v];
		}
	}

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		UnionFind uf = new UnionFind(n);
		for (int i = 0; i < m; i++) {
			uf.connect(sc.nextInt() - 1, sc.nextInt() - 1);
			sc.nextInt();
		}

		System.out.println(uf.size());
	}
}
