#include <cstdio>
#include <vector>

using namespace std;
vector<vector<int> > G;
vector<int> used;
int N, M;

void DFS(int k)
{
    used[k] = 1;
    for(auto it : G[k])
        if(!used[it])
            DFS(it);
}

int main()
{
    freopen("dfs.in", "r", stdin);
    freopen("dfs.out", "w", stdout);


    scanf("%d%d", &N, &M);
    G.resize(N + 1);
    used.resize(N + 1);

    for(int i = 1; i <= M; ++i) {
        int a, b;
        scanf("%d%d",&a,&b);
        G[a].push_back(b);
        G[b].push_back(a);
    }
    int cnt = 0;
    for(int i = 1; i <= N; ++i) {
        if(!used[i]) {
            ++cnt;
            DFS(i);
        }
    }

    printf("%d\n", cnt);


    return 0;
}