#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int k, q, a, b;
char A, B;
ll sum=0, ans=0;
priority_queue<int> l;
priority_queue<int, vector<int>, greater<int>> r;
map<int, ll> cans;
ll a1[200005], a2[200005];
void upd(int pos) {
if(l.empty()) {
l.push(pos); r.push(pos);
return;
}
if(pos < l.top()) {
sum += l.top()-pos;
l.push(pos);
l.push(pos);
r.push(l.top());
l.pop();
} else if(pos > r.top()) {
sum += pos-r.top();
r.push(pos);
r.push(pos);
l.push(r.top());
r.pop();
} else {
l.push(pos); r.push(pos);
}
}
int main() {
cin.tie(0) -> sync_with_stdio(0);
cin >> k >> q;
vector<pair<int, pair<int, int>>> vecs;
while(q--) {
cin >> A >> a >> B >> b;
if(a>b) swap(a, b);
if(A==B) {
ans += b-a;
} else {
ans++;
vecs.emplace_back(a + b, make_pair(a, b));
}
}
if(vecs.empty()) {cout << ans; return 0;}
sort(vecs.begin(), vecs.end());
for(int i=0;i<vecs.size();i++) {
upd(vecs[i].second.first);
upd(vecs[i].second.second);
a1[i] = sum;
}
if(k == 1) {cout << sum + ans; return 0;}
while(!l.empty()) l.pop(); while(!r.empty()) r.pop();
sum = 0;
ll cmin = LLONG_MAX;
for(int i=vecs.size()-1;i>=0;i--) {
cmin = min(cmin, sum + a1[i]);
upd(vecs[i].second.first);
upd(vecs[i].second.second);
}
cout << cmin + ans;
}
