#include <cstdio>
#include <vector>

using namespace std;

int viz[100005];
vector <int> G[100005];

void dfs(int u, int cc)
{
    int v;
    viz[u] = cc;
    for(int j = 0; j < G[u].size(); j++)
    {
        v = G[u][j];
        if(!viz[v])
        {
            dfs(v, cc);
        }
    }
}

int main()
{
    freopen("dfs.in", "r", stdin);
    freopen("dfs.out", "w", stdout);
    int n, m, u, v, cc = 0;
    scanf("%d%d", &n, &m);
    for(int i = 1; i <= m; i++)
    {
        scanf("%d%d", &u, &v);
        G[u].push_back(v);
        G[v].push_back(u);
    }
    for(int i = 1; i <= n; i++)
    {
        if(!viz[i])
        {
            ++cc;
            dfs(i, cc);
        }
    }
    printf("%d", cc);
    return 0;
}