#include <bits/stdc++.h>
using namespace std;
const int NMAX = 5e5;
int n, m;
vector <pair<int, bool>> graph[NMAX+1];
vector <pair<pair<int, int>, bool>> muchii;
vector <int> componenta(NMAX+1, 0), marime_componenta(NMAX+1, 0), muchii_plecare(NMAX+1, 0);
int id_comp;
map <pair<int , int>, bool> tras;
//bitset <bool> tras[NMAX+1];
void read()
{
int a, b;
bool c;
char ch;
cin>>n>>m;
for(int i=1; i<=m; i++)
{
cin>>a>>b>>ch;
if(ch == 'A') c = 1;
else c = 0;
graph[a].push_back({b, c});
graph[b].push_back({a, c});
muchii.push_back({{a, b}, c});
muchii.push_back({{b, a}, c});
}
}
void dfs(int node)
{
componenta[node] = id_comp;
marime_componenta[id_comp]++;
for(auto [next, price]:graph[node])
{
if(price==0 && componenta[next] == 0)
dfs(next);
}
}
void make_comp()
{
for(int i=1; i<=n; i++)
{
if(componenta[i] == 0)
{
id_comp++;
dfs(i);
}
}
}
int rez;
void solve()
{
for(int i=0; i<muchii.size(); i++)
{
int a = muchii[i].first.first;
int b = muchii[i].first.second;
a = componenta[a];
b = componenta[b];
if(a!=b && !(tras.find({a, b})!=tras.end()) )//tras[a][b] == 0)
{
tras[{a, b}] = 1;
//cout<<"din componenta "<<a<<" in "<<b<<'\n';
muchii_plecare[a]++;
}
}
for(int i=1; i<=id_comp; i++)
{
if(muchii_plecare[i] == id_comp-1)
{
rez = rez + marime_componenta[i];
}
}
}
void debug()
{
for(int i=1; i<=n; i++)
{
cout<<i<<" "<<componenta[i]<<'\n';
}
}
int main()
{
read();
make_comp();
solve();
//debug();
cout<<rez;
return 0;
}
/*
nodurile conectate prin trenuri sunt componente conexe
-> graf condensat
verific daca pentru fiecare componenta conexa am bus DIRECT catre oricare alta
*/
