#include <bits/stdc++.h>
#define ll long long
#define pi pair<int, char>
#define pint pair<int, int>
#define ff first
#define ss second
#define pb push_back
#define all(v) v.begin(), v.end()
#define allsir(v) v+1, v+n+1
#define inf 1e9
using namespace std;
const string file = "";
ifstream fin(file+".in");
ofstream fout(file+".out");
const int dim = 500001, mod = 1e9+7;
int n, m, a, b, i, comp[dim], sz[dim];
char c;
vector<pi> g[dim];
set<int> gc[dim];
struct muchie {
int a, b;
char c;
};
vector<muchie> lm;
void dfs(int nod, int nrc)
{
comp[nod] = nrc;
sz[nrc]++;
for (auto x : g[nod])
{
if (comp[x.ff])
continue;
if (x.ss == 'T')
dfs(x.ff, nrc);
}
}
void solve()
{
cin >> n >> m;
for (i = 1; i <= m; i++)
{
cin >> a >> b >> c;
lm.pb({a, b, c});
g[a].pb({b, c});
g[b].pb({a, c});
}
int nrc = 0;
for (i = 1; i <= n; i++)
{
if (!comp[i])
{
++nrc;
dfs(i, nrc);
}
}
for (i = 0; i < m; i++)
{
int a = lm[i].a, b = lm[i].b, c = lm[i].c;
if (c == 'A')
{
if (comp[a] == comp[b])
continue;
gc[comp[a]].insert(comp[b]);
gc[comp[b]].insert(comp[a]);
}
}
int rez = 0;
for (i = 1; i <= nrc; i++)
{
if (gc[i].size() == nrc-1)
rez += sz[i];
}
cout << rez;
}
int main()
{
int t = 1;
ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
//cin >> t;
while (t--)
solve();
return 0;
}
