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.IOException;
import java.io.InputStream;
import java.util.*;
 
public class Main {
	
    public static void main(String[] args) {
    	FastScanner sc = new FastScanner();
 
    	int n = sc.nextInt();
    	int m = sc.nextInt();
    	UnionFindTree t = new UnionFindTree(n);

    	for(int i=0;i<m;i++){
    		t.unite(sc.nextInt()-1, sc.nextInt()-1);
    		sc.nextInt();
    	}
    
    	System.out.println(t.total());
    }
    
    
    
}

class UnionFindTree {
	int[] par;
	int[] rank;
	int[] peers; //仲間の数
	
	public UnionFindTree(int n){
		par = new int[n];
		rank = new int[n];
		peers = new int[n];
		
		for(int i=0;i<n;i++){
			par[i] = i;
			peers[i] = 1;
		}
	}
	
	//木の根を求める
	int find(int x){
		if(par[x] == x){
			return x;
		}
		else{
			return par[x] = find(par[x]);
		}
	}
	
	//xとyの属する集合を併合
	void unite(int x, int y){
		int px = find(x);
		int py = find(y);
		
		if(px == py){
			return;
		}
		else if(rank[px] < rank[py]){
			peers[py] += peers[px];
			par[px] = py;

		}
		else{
			peers[px] += peers[py];
			par[py] = px;
			if(rank[px]==rank[py]){
				rank[px]++;
			}
		}
		
	}
	
	//xとyが同じ集合に属するか
	boolean isEquivalent(int x, int y){
		return find(x) == find(y);
	}
	
	//xの仲間の数を求める
	int peersnum(int x){
		return peers[find(x)];
	}
	
	//総集合数
	int total(){
		boolean[] iss = new boolean[par.length];
		int sum = 0;
		for(int i=0;i<par.length;i++){
			int mo = find(i);
			if(iss[mo]){
				
			}
			else{
				iss[mo] = true;
				sum += 1;
			}
		}
		return sum;
	}
	
}
 
class FastScanner {
    private final InputStream in = System.in;
    private final byte[] buffer = new byte[1024];
    private int ptr = 0;
    private int buflen = 0;
    private boolean hasNextByte() {
        if (ptr < buflen) {
            return true;
        }else{
            ptr = 0;
            try {
                buflen = in.read(buffer);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (buflen <= 0) {
                return false;
            }
        }
        return true;
    }
    private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
    private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
    public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
    public String next() {
        if (!hasNext()) throw new NoSuchElementException();
        StringBuilder sb = new StringBuilder();
        int b = readByte();
        while(isPrintableChar(b)) {
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }
    public long nextLong() {
        if (!hasNext()) throw new NoSuchElementException();
        long n = 0;
        boolean minus = false;
        int b = readByte();
        if (b == '-') {
            minus = true;
            b = readByte();
        }
        if (b < '0' || '9' < b) {
            throw new NumberFormatException();
        }
        while(true){
            if ('0' <= b && b <= '9') {
                n *= 10;
                n += b - '0';
            }else if(b == -1 || !isPrintableChar(b)){
                return minus ? -n : n;
            }else{
                throw new NumberFormatException();
            }
            b = readByte();
        }
    }
    public int nextInt() {
        long nl = nextLong();
        if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
        return (int) nl;
    }
    public double nextDouble() { return Double.parseDouble(next());}
}