#include <bits/stdc++.h>
using namespace std;
vector<int> parent, sizee;
int getroot(int v)
{
if (parent[v] == v) return v;
return parent[v] = getroot(parent[v]);
}
void union_set(int a, int b)
{
a = getroot(a);
b = getroot(b);
if (a != b)
{
if (sizee[a] < sizee[b]) swap(a, b);
parent[b] = a;
sizee[a] += sizee[b];
}
}
int main()
{
cin.tie(nullptr);
ios_base :: sync_with_stdio(false);
int N, M;
cin >> N >> M;
vector<pair<int,int>> cfr, stb;
cfr.reserve(M);
stb.reserve(M);
for(int i = 1; i <= M; i ++)
{
int a, b;
char t;
cin >> a >> b >> t;
if(t == 'T')
{
cfr.push_back({a, b});
}
else
{
stb.push_back({a, b});
}
}
parent.resize(N + 1);
sizee.resize(N + 1, 1);
for(int i = 1; i <= N; i++)
{
parent[i] = i;
}
for (auto & i : cfr)
{
union_set(i.first, i.second);
}
unordered_map<int,int> m;
m.reserve(N);
vector<int> which(N + 1, -1);
int cnt = 0;
for(int v = 1; v <= N; v ++)
{
int r = getroot(v);
if(!m.count(r))
{
m[r] = cnt ++;
}
which[v] = m[r];
}
vector<int> marime(cnt, 0);
for(int i = 1; i <= N; i ++)
{
marime[which[i]]++;
}
vector<unordered_set<int>> adj(cnt);
for (auto & i : stb)
{
int x = which[i.first];
int y = which[i.second];
if (x != y)
{
adj[x].insert(y);
adj[y].insert(x);
}
}
int ans = 0;
for(int i = 0; i < cnt; i ++)
{
if(adj[i].size() == cnt - 1)
{
ans += marime[i];
}
}
cout << ans << '\n';
return 0;
}
