#include <iostream>
#include <vector>
#include <string.h>
#include <stdio.h>

void DFS(int node, std::vector<int>g[], int visited[]) {
	
	visited[node] = 1;
	for (unsigned int i = 0; i < g[node].size(); i++) {
		if (!visited[g[node][i]]) {
			DFS(g[node][i], g, visited);
		}
	}
}

int main() {

	int n, m, x, y;
	
	FILE* fin = fopen("dfs.in", "r");
	FILE* fout = fopen("dfs.out", "w");
	
	fscanf(fin, "%d %d", &n, &m);
	
	std::vector<int> graf[n + 1];
	int visited[n + 1];
	
	memset(visited, 0, sizeof(int) * (n + 1));
	
	for (int i = 1; i <= m; i++) {
		fscanf(fin, "%d %d", &x, &y);
		graf[x].push_back(y);
		graf[y].push_back(x);
	}
	
	fclose(fin);
	int comp = 0;
	
	for (int i = 1; i <= n; i++) {
		if (!visited[i]) {
			DFS(i, graf, visited);
			comp++;
		} 
	}
	
	fprintf(fout, "%d", comp);
	fclose(fout);
}