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.*;

public class Main {

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

}

class UnionFind {

    int length;
    int[] parent;
    int[] deep;
    int rootX, rootY;

    public UnionFind(int length) {
        this.length = length;
        parent = new int[length];
        for (int i = 0; i < length; i++) {
            parent[i] = i;
        }
        deep = new int[length];
    }

    public int getRoot(int x) {
        if (parent[x] == x) {
            return x;
        } else {
            return parent[x] = getRoot(parent[x]);
        }
    }

    public void makeSame(int x, int y) {
        rootX = getRoot(x);
        rootY = getRoot(y);
        if (rootX == rootY) {
            return;
        } else if (deep[rootX] > deep[rootY]) {
            parent[rootY] = parent[rootX];
        } else {
            parent[rootX] = parent[rootY];
            if (deep[rootX] == deep[rootY]) {
                deep[rootY]++;
            }
        }
        length--;
    }

    public boolean isSame(int x, int y) {
        return getRoot(x) == getRoot(y);
    }
}