#include <bits/stdc++.h>
#define f first
#define s second
using namespace std;
#define int long long
const int maxn = 5e5 + 69;
vector<int> p(maxn), sz(maxn);
vector<int> deg(maxn);
int find_set(int v) {
if(p[v] == v)
return v;
return p[v] = find_set(p[v]);
}
void unite(int a, int b) {
a = find_set(a);
b = find_set(b);
if(a != b) {
if(sz[a] < sz[b])
swap(a, b);
p[b] = a;
sz[a] += sz[b];
}
}
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int tt = 1;
//cin >> tt;
while(tt--) {
int n, m;
cin >> n >> m;
vector<pair<int, int>> edges;
for(int i = 1;i <= n;i++) {
p[i] = i;
sz[i] = 1;
}
for(int i = 0;i < m;i++) {
int a, b;
char c;
cin >> a >> b >> c;
if(c == 'T')
unite(a, b);
else
edges.push_back({a, b});
}
set<int> kurac;
for(int i = 1;i <= n;i++)
kurac.insert(find_set(i));
int c = kurac.size();
int ans = 0;
set<pair<int, int>> bio;
for(auto x : edges) {
int a = find_set(x.f);
int b = find_set(x.s);
if(a > b)
swap(a, b);
if(bio.count({a, b}) || a == b)
continue;
else {
bio.insert({a, b});
deg[a]++;
deg[b]++;
}
}
for(auto x : kurac)
ans += (deg[x] >= c - 1 ? sz[x] : 0);
if(c == 1)
ans = n;
cout << ans;
}
return 0;
}
