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.IOException;
import java.io.InputStreamReader;


public class Main{
  public static void main(String[] args) throws IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    String[] line1 = br.readLine().split(" ");
    int numOfCards = Integer.parseInt(line1[0]);
    int numOfHints = Integer.parseInt(line1[1]);
    
    UnionFind tree = new UnionFind(numOfCards);
    
    int x;
    int y;
    
    for(int i=0; i<numOfHints; i++){
      String[] hint = br.readLine().split(" ");
      x = Integer.parseInt(hint[0])-1;
      y = Integer.parseInt(hint[1])-1;
      
      if(!tree.whetherSameRoot(x, y)){
        tree.uniteNode(x, y);
      }
    }
    System.out.println(tree.getNumOfRoot());
  }
}

class UnionFind{
  int[] par;
  UnionFind(int numNode){
    par = new int[numNode];
    for(int i=0; i<numNode; i++){
      par[i] = i;
    }
  }
  
  int getRoot(int nodeIndex){
    if(par[nodeIndex] == nodeIndex){
      return nodeIndex;
    }else{
      return par[nodeIndex] = getRoot(par[nodeIndex]);
    }
  }
  
  void uniteNode(int nodeA, int nodeB){
    if(!whetherSameRoot(nodeA, nodeB)){
      par[getRoot(nodeA)] = getRoot(nodeB);
    }
  }
  
  boolean whetherSameRoot(int nodeA, int nodeB){
    return getRoot(nodeA) == getRoot(nodeB);
  }
  
  int getNumOfRoot(){
    int result = 0;
    for(int i=0; i<par.length; i++){
      if(par[i] == i){
        result++;
      }
    }
    return result;
  }
}