#include <fstream>
#include <vector>
#define maxn 100010

using namespace std;

vector<int> a[maxn];
int n, m;
bool seen[maxn];
ifstream in("dfs.in");
ofstream out("dfs.out");

void dfs(int node) {
    seen[node] = true;
    for(int i = 0;i < a[node].size();i++)
        if(!seen[a[node][i]])
            dfs(a[node][i]);
}
int main() {
    in>>n>>m;
    int sol = 0,x,y;

    for(int i = 0;i < m; i++) {
        in>>x>>y;
        a[x].push_back(y);
        a[y].push_back(x);
    }

    for(int i = 1; i <=n; i++) {
        if(!seen[i]) {
            dfs(i);
            sol++;
        }
    }

    out<<sol;

}