#D951. 1 or 2

    ID: 788 Type: Default 2000ms 1073MiB

1 or 2

1 or 2

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

inputFormat

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

outputFormat

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

样例

100000 1
1 100000 100
99999