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
N, M = map(int, input().split())

nlist = [] * N
for i in range(N):
    nlist.append([])
for i in range(M):
    X, Y, Z = map(int, input().split())
    X -= 1
    Y -= 1
    nlist[X].append(Y)
    nlist[Y].append(X)

visit = [False] * N
ans = 0
for i in range(N):
    if visit[i]:
        continue
    ans += 1
    visit[i] = True
    vlist = nlist[i]
    while vlist:
        tmp = []
        for to in vlist:
            if visit[to]:
                continue
            visit[to] = True
            tmp.extend(nlist[to])
        vlist = tmp

print(ans)
