#include <stdio.h>
#include <vector>
#include <queue>
#define NMAX 100000

using namespace std;

FILE* fin, * fout;

vector<int> g[NMAX + 1];
int n, m;
int viz[NMAX + 1] = { 0 };

void DFS(int x) {
    viz[x] = 1;
    for (int y : g[x]) {
        if (!viz[y])
            DFS(y);
    }
}

int main()
{
    fin = fopen("dfs.in", "r");
    fout = fopen("dfs.out", "w");

    fscanf(fin, "%i %i", &n, &m);
    while (m--) {
        int x, y;
        fscanf(fin, "%i %i", &x, &y);
        g[x].push_back(y);
        g[y].push_back(x);
    }

    int nr = 0;
    for (int i = 1;i <= n;++i) {
        if (!viz[i]) {
            ++nr;
            DFS(i);
        }
    }

    fprintf(fout,"%i", nr);
  
    return 0;
}