#include <bits/stdc++.h>
#define ar array
using namespace std;
struct union_find {
int n;
vector<int> par, size;
union_find(int _n) : n(_n), par(n+1), size(n+1, 1) {
for(int i=1; i<=n; i++) par[i] = i;
}
int find(int u) {
if(u == par[u]) return u;
return par[u] = find(par[u]);
}
void uni(int a, int b) {
a = find(a); b = find(b);
if(a == b) return ;
if(size[a] < size[b]) swap(a, b);
size[a] += size[b];
par[b] = a;
}
int get_size(int u) {
return size[find(u)];
}
};
signed main() {
int n, m; cin >> n >> m;
union_find dsu(n);
vector<ar<int, 2> > E;
for(int i=1; i<=m; i++) {
int a, b; char t;
cin >> a >> b >> t;
if(t == 'T') dsu.uni(a, b);
else E.push_back({ a, b });
}
vector< set<int> > G(n+1);
for(auto [a, b] : E) {
a = dsu.find(a);
b = dsu.find(b);
G[a].insert(b);
G[b].insert(a);
}
int ans = 0;
for(int i=1; i<=n; i++) {
if(i != dsu.find(i)) continue;
int cnt = dsu.get_size(i);
for(int j : G[i]) cnt += dsu.get_size(j);
if(cnt == n) ans += dsu.get_size(i);
}
cout << ans << '\n';
}
