#include <bits/stdc++.h>
using namespace std;
const int nx=5e5+5;
int n, m, sz[nx], g[nx], vs[nx], u, v, cnt, dp[nx], mx, res;
char t;
vector<int> d[nx];
vector<pair<int, int>> edg;
set<int> s[nx];
void dfs(int u, int hd)
{
vs[u]=1;
g[u]=hd;
sz[hd]++;
for (auto v:d[u]) if (!vs[v]) dfs(v, hd);
}
int main()
{
cin.tie(NULL)->sync_with_stdio(false);
cin>>n>>m;
for (int i=1; i<=m; i++)
{
cin>>u>>v>>t;
if (t=='T') d[u].push_back(v), d[v].push_back(u);
else edg.push_back({u, v});
}
for (int i=1; i<=n; i++) if (!vs[i]) dfs(i, ++cnt);
for (auto [u, v]:edg) if (g[u]!=g[v]) s[g[u]].insert(g[v]), s[g[v]].insert(g[u]);
for (int i=1; i<=cnt; i++)
{
dp[i]=sz[i];
for (auto v:s[i]) dp[i]+=sz[v];
}
//for (int i=1; i<=n; i++) cout<<"g "<<i<<' '<<g[i]<<'\n';
//for (int i=1; i<=cnt; i++) cout<<i<<' '<<sz[i]<<' '<<dp[i]<<'\n';
for (int i=1; i<=cnt; i++) if (dp[i]==n) res+=sz[i];
cout<<res;
}
