#include <cstdio>
#include <vector>

using namespace std;

const int nmx = 100005;

int n, m, suma;
vector <int> G[nmx];
bool viz[nmx];

void dfs(int nod){
    viz[nod] = 1;
    for(vector<int>::iterator it = G[nod].begin(); it != G[nod].end(); ++it)
        if(not viz[*it])
            dfs(*it);
}

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

    scanf("%d %d", &n, &m);
    for(int i = 0; i < m; ++i){
        static int x, y;
        scanf("%d %d", &x, &y);
        G[x].push_back(y);
        G[y].push_back(x);
    }

    for(int i = 1; i <= n; ++i)
        if(not viz[i]){
            ++ suma;
            dfs(i);
        }

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

    return 0;
}