After heavy rain, a district sets up N rescue camps. Some pairs of camps are connected by usable roads. Two camps belong to the same rescue region if a volunteer can travel from one to the other using one or more usable roads.

Your task is to count how many separate rescue regions exist.

The first line contains two integers KaTeX can only parse string typed expression and KaTeX can only parse string typed expression — the number of camps and usable roads.

Each of the next KaTeX can only parse string typed expression lines contains two integers KaTeX can only parse string typed expression and KaTeX can only parse string typed expression, meaning camp KaTeX can only parse string typed expression and camp KaTeX can only parse string typed expression are connected by a two-way road.

Print a single integer — the number of separate rescue regions.