#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
int n,m,viz[100001],i,x,y,nr;
vector <int> L[100001];
void dfs(int x)
{
    viz[x]=1;
    for(int k=0; k<L[x].size(); k++)
        if(viz[L[x][k]]==0)
            dfs(L[x][k]);
}

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);
    L[x].push_back(y);
    L[y].push_back(x);
}
for(i=1; i<=n; i++)
    if(viz[i]==0)
{
    nr++;
    dfs(i);
}
printf("%d", nr);


    return 0;
}