#include <fstream>

using namespace std;
int n,k,x,i,j,v[100],a[100][100],m,nr;
ifstream f("dfs.in");
ofstream g("dfs.out");

void citire()
{f>>n>>m;
for(x=1;x<=m;x++)
    {f>>i>>j;
        a[i][j]=1;
a[j][i]=1;}
}
void dfs(int k)
{int i;
    v[k]=1;
for(i=1;i<=n;i++)
    if(a[k][i]==1 && v[i]==0)
    dfs(i);
}
int main()
{citire();
for(i=1;i<=n;i++)
if(!v[i]) {nr++;
            dfs(i);}
g<<nr;
    return 0;
}