Description

You are given an integer n representing the number of nodes, and an array edges where edges[i] = [a, b] indicates an undirected edge between nodes a and b.

Return the total number of connected components in the graph.

Input format:

• Line 1: Integer n
• Line 2: Edges array as JSON

Examples

Input:
5
[[0,1],[1,2],[3,4]]

Output:
2

Input:
5
[[0,1],[1,2],[2,3],[3,4]]

Output:
1

Note:

Print only the integer result.