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.*;
import java.lang.*;
class UnionFind{
    int size;
    int[] parent;
    int[] height;
    public UnionFind(int size){
        this.size = size;
        parent = new int[size];
        height = new int[size];
        for(int i=0;i<size;i++){
            parent[i]=i;
            height[i]=0;
        }
    }
    private boolean isRoot(int node){
        return node==parent[node];
    }
    private int getRoot(int node){
        if(isRoot(node)) return node;
        else{
            parent[node] = getRoot(parent[node]);
            return parent[node];
        }
    }
    public void union(int node1, int node2){
        if(height[node1]>height[node2])parent[getRoot(node2)] = getRoot(node1);
        else parent[getRoot(node1)] = getRoot(node2);
    }
    public boolean find(int node1, int node2){
        return getRoot(node1)==getRoot(node2);
    }
    public int countGroup(){
        int ans = 0;
        for(int i=0;i<size;i++) if(isRoot(i)) ans++;
        return ans;
    }
}

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        int M = sc.nextInt();
        UnionFind G = new UnionFind(N);
        for(int m=0; m<M; m++){
            int X = sc.nextInt()-1;
            int Y = sc.nextInt()-1;
            int Z = sc.nextInt();
            G.union(X,Y);
        }
        System.out.println(G.countGroup());

    }
}
