#include <cstdio>
#include <vector>
#include <stack>

#define NMAX 100005

using namespace std;

bool visited[NMAX];
vector<int> Graph[NMAX];

void dfs(int node) {

    stack<int> s;
    s.push(node);
    visited[node]=true;
    while(!s.empty()) {
        int nodeTop=s.top();
        s.pop();
        for(int vecin : Graph[nodeTop]) {
            if(!visited[vecin]) {
                visited[vecin]=true;
                s.push(vecin);
            }
        }
    }

}

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

    int numberOfNodes,numberOfEdges;

    scanf("%d %d",&numberOfNodes,&numberOfEdges);
    for(int i=0;i<numberOfEdges;i++) {
        int x,y;
        scanf("%d %d",&x,&y);
        Graph[x].push_back(y);
        Graph[y].push_back(x);
    }
    int nrConnectedComp=0;
    for(int i=1;i<=numberOfNodes;i++) {
        if(!visited[i]) {
            nrConnectedComp++;
            dfs(i);
        }
    }
    printf("%d\n",nrConnectedComp);
    return 0;
}