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

#define NMAX 100005

using namespace std;

void dfs(int vizitat[], vector<int> G[], int i, int cc) {
    vizitat[i] = cc;
    for (int j = 0; j < G[i].size(); j++) {
        int v = G[i][j];
        if (vizitat[v] == 0) {
            dfs(vizitat, G, v, cc);
        }
    }
}

int main() {
    FILE *fin, *fout;
    fin = fopen("dfs.in", "rt");
    fout = fopen("dfs.out", "wb");
    int n, m;
    fscanf(fin, "%d%d", &n, &m);
    vector<int> G[NMAX];
    for (int i = 0; i < m; i++) {
        int x, y;
        fscanf(fin, "%d%d", &x, &y);
        G[x].push_back(y);
        G[y].push_back(x);
    }
    int cc = 0;
    int vizitat[NMAX]; memset(vizitat, 0, NMAX);
    for (int i = 1; i <= n; i++) {
        if (vizitat[i] == 0) {
            cc++;
            dfs(vizitat, G, i, cc);
        }
    }
    fprintf(fout, "%d\n", cc);
    fclose(fin);
    fclose(fout);
    return 0    ;
}