#include <stdio.h>
#include <vector>

using namespace std;

const int MAX = 1050;

bool visited[MAX]; int n, m, a, b, contor;
vector<int> v[MAX];

void dfs(int x)
{
    visited[x] = true;
    for(size_t i = 0; i < v[x].size(); i++)
        if(!visited[v[x][i]])
            dfs(v[x][i]);
}

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", &a, &b);
        v[a].push_back(b); v[b].push_back(a);
    }fclose(stdin);
    for(int i = 1; i <= n; i++)
        if(!visited[i])
        {
            contor++;
            dfs(i);
        }
    printf("%d\n", contor);
    fclose(stdout);
    return 0;
}