#include <cstdio>
#include <vector>

using namespace std;

vector <int>g[100005];

int x, y, n, m;
int viz[100005];

void dfs(int x)
{
    viz[x]=1;
    for(auto &v:g[x])
        if(!viz[v])
            dfs(v);
}

int main()
{

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

    scanf("%d %d", &n, &m);
    for(int i=1; i<=m; i++)
    {
        scanf("%d %d", &x, &y);
        g[x].push_back(y);
        g[y].push_back(x);
    }
    int nr=0;
    for(int i=1; i<=n; i++)
    {
        if(!viz[i])
        {
            dfs(i);
            nr++;
        }
    }
    printf("%d", nr);
    return 0;
}