#include <iostream>
#include <algorithm>
#include <cmath>
#include <vector>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <queue>
#include <cassert>
#include <string>
#include <cstring>
#include <bitset>
#include <random>
#include <chrono>
#define FOR(i, a, b) for(int i = a; i < (int) b; i++)
#define F0R(i, a) FOR (i, 0, a)
#define ROF(i, a, b) for(int i = a; i >= (int) b; i--)
#define R0F(i, a) ROF(i, a, 0)
#define GO(i, a) for (auto i : a)
#define rsz resize
#define eb emplace_back
#define pb push_back
#define sz(x) (int) x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define f first
#define s second
using namespace std;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<pii> vpii;
typedef vector<vi> vvi;
typedef vector<vpii> vvpii;
typedef long long i64;
typedef vector<i64> vi64;
typedef vector<vi64> vvi64;
typedef pair<i64, i64> pi64;
typedef vector<pi64> vpi64;
const int dr[] = {+1, -1, +0, +0, +1, -1, +1, -1};
const int dc[] = {+0, +0, +1, -1, +1, -1, -1, +1};
const int ms[] = {+31, +29, +31, 30, +31, +30, +31, +31, +30, +31, +30, +31};
const int N = 5e5 + 5;
vvi g (N);
vvi bus (N);
vi color (N, -1);
bool vis [N], valid_color [N];
int group = 0;
void dfs (int node) {
vis[node] = true;
color[node] = group;
GO (to, g[node]) {
if (!vis[to]) {
vis[to] = true;
dfs (to);
}
}
}
set<int> unique_color;
void solve (int node) {
vis[node] = true;
unique_color.insert(color[node]);
GO (to, bus[node]) {
unique_color.insert(color[to]);
}
GO (to, g[node]) {
if (!vis[to]) {
vis[to] = true;
solve (to);
}
}
}
int main () {
ios::sync_with_stdio(0);
cin.tie(0);
int n, m;
cin >> n >> m;
F0R (i, m) {
char tipo;
int st, et;
cin >> st >> et >> tipo;
--st; --et;
if (tipo == 'T') {
g[st].eb(et);
g[et].eb(st);
} else {
bus[st].eb(et);
bus[et].eb(st);
}
}
F0R (i, n) {
if (!vis[i]) {
dfs (i);
++group;
}
}
int res = 0;
memset (vis, 0, sizeof(vis));
F0R (i, n) {
if (!vis[i]) {
unique_color.clear();
solve (i);
if (sz(unique_color) == group) valid_color[color[i]] = true;
}
}
F0R (i, n) {
if (valid_color[color[i]]) ++res;
}
cout << res << '\n';
return 0;
}
