#include <cstdio>
#include <vector>
#include <queue>
#include <cstring>
using namespace std;

int n, m, i, x, y, nr;
bool ap[100002];
vector<int>G[100002];

void dfs (int x)
{
    ap[x]=1;
    for (int i=0; i<G[x].size(); i++){
        if (ap[G[x][i]]==0) dfs(G[x][i]);
    }
}

int main ()
{

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

    scanf("%d%d", &n, &m);

    for (i=1; i<=m; i++){
        scanf("%d%d", &x, &y);
        G[x].push_back(y);
        G[y].push_back(x);
    }

    for (i=1; i<=n; i++){
        if (ap[i]==0){
            nr++;
            dfs(i);
        }
    }
    printf("%d", nr);
    return 0;
}