#include <fstream>
#include <vector>

constexpr int kMaxN = 100000;

int n, m;
bool visited[kMaxN+1];
std::vector<int> edges[kMaxN+1];

void dfs(int x) {
    visited[x] = true;
    for(int y : edges[x]) {
        if(!visited[y]) dfs(y);
    }
}

int main()
{
    std::ifstream in("dfs.in");
    std::ofstream out("dfs.out");
    int n_components = 0;
    in>>n>>m;
    for(int x, y, i = 1; i <= m; ++i) {
        in>>x>>y;
        edges[x].push_back(y);
        edges[y].push_back(x);
    }
    for(int i = 1; i <= n; ++i) {
        if(!visited[i]) {
            ++n_components;
            dfs(i);
        }
    }
    out<<n_components<<'\n';
    return 0;
}