#include <fstream>
#include <vector>
#define DIM 100002

using namespace std;

ifstream in ("file.in");
ofstream out("file.out");

int n, m, x, y,comp;
bool viz[DIM];

vector<int> graf[DIM];

void dfs(int nod) {
    viz[nod] = 1;
    for(int i = 0; i < graf[nod].size(); i ++){
        if(viz[graf[nod][i]]==0){
            dfs(graf[nod][i]);
        }
    }
}

int main(int argc, const char * argv[]) {
    
    in>>n>>m;
    for(int i=1;i<=m;i++){
        in>>x>>y;
        graf[x].push_back(y);
        graf[y].push_back(x);
        
    }
    
    for(int i=1;i<=n;i++){
        if(viz[i]==0){
            dfs(i);
            comp++;
        }
    }
    
    out<<comp;
    
    return 0;
}