#include <iostream>
#include <set>
#include <vector>
using namespace std;
int n, m;
vector<int> graf[500005];
vector<pair<int, int>> bus;
int dad[500005];
int sizeC[500005];
set<int> compCon[500005];
int getDad(int nod)
{
if (dad[nod] == 0)
{
return nod;
}
else
{
return dad[nod] = getDad(dad[nod]);
}
}
void uni(int nod1, int nod2)
{
int dad1 = getDad(nod1);
int dad2 = getDad(nod2);
if (dad1 != dad2)
{
dad[dad1] = dad2;
sizeC[dad2] = sizeC[dad1] + sizeC[dad2];
}
}
int main()
{
cin >> n >> m;
int x, y;
char z;
for (int i = 0; i <= n; i++)
{
sizeC[i] = 1;
}
for (int i = 0; i < m; i++)
{
cin >> x >> y >> z;
if (z == 'T')
{
uni(x, y);
}
else
{
bus.push_back({ x, y });
}
}
int nrCompCon = 0;
for (int i = 1; i <= n; i++)
{
if (dad[i] == 0)
{
nrCompCon++;
}
}
for (int i = 0; i < bus.size(); i++)
{
if (getDad(bus[i].first) != getDad(bus[i].second))
{
compCon[getDad(bus[i].first)].insert(getDad(bus[i].second));
compCon[getDad(bus[i].second)].insert(getDad(bus[i].first));
}
}
int total = 0;
for (int i = 1; i <= n; i++)
{
if (dad[i] == 0 && compCon[i].size() == nrCompCon -1)
{
total += sizeC[i];
}
}
cout << total;
}
