#include <cstdio>
#include <vector>
#define MAX 100001
using namespace std;
vector<int>g[MAX];
int n,nr=0;
bool viz[MAX];

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

int main(){
    int x,y,i,m;
    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);}
    for(int i=1;i<=n;i++)
    if(!viz[i]){
        nr++;
        dfs(i);}
    printf("%d\n",nr);
}