#include <bits/stdc++.h>
using namespace std;
const int mxN = 5e5 + 100;
int par[mxN], sz[mxN], deg[mxN], par2[mxN], sz2[mxN];
set<pair<int, int>> bus;
int find(int u){
if(u == par[u]) return u;
return par[u] = find(par[u]);
}
void unite(int u, int v){
u = find(u), v = find(v);
if(u == v) return;
par[u] = v, sz[v] += sz[u];
}
int find2(int u){
if(u == par2[u]) return u;
return par2[u] = find2(par2[u]);
}
void unite2(int u, int v){
u = find2(u), v = find2(v);
if(u == v) return;
//cout << "uni" << u << v << endl;
par2[u] = v, sz2[v] += sz2[u];
}
int main(){
int n, m, u, v, ans = 0;
cin >> n >> m;
char ch;
for(int i = 1; i <= n; ++i) sz[i] = 1, par[i] = i, par2[i] = i;
for(int i = 0; i < m; ++i){
cin >> u >> v >> ch;
if(u > v) swap(u, v);
if(ch == 'T') unite(u, v);
else bus.insert({u, v});
}
int nn = 0;
for(int i = 1; i <= n; ++i) nn += par[i] == i;
if(sz[find(1)] == n){
cout << n << "\n";
return 0;
}
for(int i = 1; i <= n; ++i) sz2[i] = sz[i], par2[i] = par[i];
for(auto it : bus) {
if(find(it.first) != find(it.second) && find2(find(it.first)) != find2(find(it.second))){
++deg[find(it.first)], ++deg[find(it.second)];
//unite(it.first, it.second);
unite2(find(it.first), find(it.second));
//cout << find(it.first) << " " << find(it.second) << endl;
}
}
//cout << sz2[find2(1)] << endl;
if(sz2[find2(1)] != n){
cout << "0\n";
return 0;
}
//cout << nn - 1 << endl;
for(int i = 1; i <= n; ++i){
if(find(i) == i && deg[i] == (nn - 1)){
ans += sz[find(i)];
//cout << i << endl;
}
}
cout << ans << "\n";
return 0;
}
