/*************************************
* author: marvinthang *
* created: 25.11.2023 08:57:19 *
*************************************/
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define left ___left
#define right ___right
#define TIME (1.0 * clock() / CLOCKS_PER_SEC)
#define MASK(i) (1LL << (i))
#define BIT(x, i) ((x) >> (i) & 1)
#define __builtin_popcount __builtin_popcountll
#define ALL(v) (v).begin(), (v).end()
#define REP(i, n) for (int i = 0, _n = (n); i < _n; ++i)
#define REPD(i, n) for (int i = (n); i-- > 0; )
#define FOR(i, a, b) for (int i = (a), _b = (b); i < _b; ++i)
#define FORD(i, b, a) for (int i = (b), _a = (a); --i >= _a; )
#define FORE(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORDE(i, b, a) for (int i = (b), _a = (a); i >= _a; --i)
#define scan_op(...) istream & operator >> (istream &in, __VA_ARGS__ &u)
#define print_op(...) ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#ifdef LOCAL
#include "debug.h"
#else
#define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
#define DB(...) 23
#define db(...) 23
#define debug(...) 23
#endif
template <class U, class V> scan_op(pair <U, V>) { return in >> u.first >> u.second; }
template <class T> scan_op(vector <T>) { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class U, class V> print_op(pair <U, V>) { return out << '(' << u.first << ", " << u.second << ')'; }
template <size_t i, class T> ostream & print_tuple_utils(ostream &out, const T &tup) { if constexpr(i == tuple_size<T>::value) return out << ")"; else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); }
template <class ...U> print_op(tuple<U...>) { return print_tuple_utils<0, tuple<U...>>(out, u); }
template <class Con, class = decltype(begin(declval<Con>()))> typename enable_if <!is_same<Con, string>::value, ostream&>::type operator << (ostream &out, const Con &con) { out << '{'; for (__typeof(con.begin()) it = con.begin(); it != con.end(); ++it) out << (it == con.begin() ? "" : ", ") << *it; return out << '}'; }
template <class A, class B> bool minimize(A &a, B b) { if (a > b) { a = b; return true; } return false; }
template <class A, class B> bool maximize(A &a, B b) { if (a < b) { a = b; return true; } return false; }
// end of template
const long long INF = 1e18;
void process(void) {
int k, n; cin >> k >> n;
vector <pair <int, int>> segments;
long long res = 0;
REP(i, n) {
char p, q; int s, t; cin >> p >> s >> q >> t;
if (s > t) swap(s, t);
if (p == q) res += t - s;
else {
res += t - s + 1;
segments.emplace_back(s, t);
}
}
if (segments.empty()) return void(cout << res << '\n');
vector <int> tl, tr, pos;
for (auto [l, r]: segments) {
pos.push_back(l);
tl.push_back(l);
pos.push_back(r);
tr.push_back(r);
}
sort(ALL(pos)); pos.erase(unique(ALL(pos)), pos.end());
sort(ALL(tl)); sort(ALL(tr));
vector <long long> sum_tl(tl.size() + 1), sum_tr(tr.size() + 1);
REPD(i, tl.size()) sum_tl[i] = sum_tl[i + 1] + tl[i];
REP(i, tr.size()) sum_tr[i + 1] = sum_tr[i] + tr[i];
long long ans = INF;
for (int x: pos) {
int p = upper_bound(ALL(tl), x) - tl.begin();
int q = lower_bound(ALL(tr), x) - tr.begin();
minimize(ans, sum_tl[p] - sum_tr[q] + 1LL * x * (q - (int) tl.size() + p));
}
if (k == 2) {
REP(r, pos.size()) REP(l, r) {
int p = upper_bound(ALL(tl), pos[r]) - tl.begin();
int q = lower_bound(ALL(tr), pos[l]) - tr.begin();
long long cur = sum_tl[p] - 1LL * pos[r] * ((int) tl.size() - p) + 1LL * pos[l] * q - sum_tr[q];
for (auto [x, y]: segments) if (pos[l] < x && y < pos[r]) cur += min(x - pos[l], pos[r] - y);
minimize(ans, cur);
}
}
cout << res + ans * 2 << '\n';
}
int main(void) {
ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
file("bridge");
// int t; cin >> t; while (t--)
process();
// cerr << "Time elapsed: " << TIME << " s.\n";
return (0^0);
}
