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
#include<iostream>
using namespace std;

int N, P[100005];

void connect(int tail, int head) {
  P[tail] = head;
}

int find(int node) {
  int cur_node = node, p = P[node];
  while (cur_node != p) {
    P[cur_node] = P[p];
    cur_node = p;
    p = P[p];
  }
  return cur_node;
}

int main() {
  int M, x, y, z, root_x;
  cin >> N >> M;
  for (int i = 0; i < N; i++) P[i] = i;
  int res = N;
  for (int c = 0; c < M; c++) {
    cin >> x >> y >> z; x--; y--;
    if ((root_x = find(x)) != find(y)) {
      connect(root_x, y); res--;
    }
  }
  cout << res << endl;
}