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 <bits/stdc++.h>

using namespace std;

int p[100010];

void init() {
    for (int i = 0; i < 100010; ++i)
        p[i] = i;
}

int f(int x) {
    return x == p[x] ? x : p[x] = f(p[x]);
}

void merge(int x,int y) {
    p[f(y)] = p[f(x)];
}

int main() {
    int n,m;
    cin >> n >> m;
    init();
    for (int i = 0; i < m; ++i) {
        int x,y,z;
        cin >> x >> y >> z;
        merge(x,y);
    }

    int ans = 0;

    
    for (int i = 1; i <= n; ++i)
        ans += f(i) == i;

    cout << ans << "\n";

    return 0;
}
