#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define is insert
#define ll long long
#define V vector
#define MS multiset
#define PL pair<ll, ll>
#define F first
#define S second
#define PQ priority_queue
#define f0r(i, begin, finish) for (ll i = begin; i < finish; i ++)
#define For(i, finish, begin) for (ll i = finish; i > begin; i --)
#define all(x) x.begin(), x.end()
#define INF 1000000000000000000
#define inf 1000000000
#define MOD 1000000007
#define len(x) (ll)x.size()
#define fileread(file) ifstream fin; fin.open((string)file + ".in"); ofstream fout; fout.open((string)file + ".out")
#define fastio ios_base::sync_with_stdio(0); cin.tie(nullptr)
template<typename T> istream& operator>>(istream& in, V<T>& a) {for(auto &x : a) in >> x; return in;};
template<typename T> ostream& operator<<(ostream& out, V<T>& a) {for(auto &x : a) out << x << ' '; return out;};
int main () {
int K, N; cin >> K >> N;
ll tot = 0;
if (K == 1) {
V<ll> crits;
V<PL> r;
f0r (i, 0, N) {
char a, b;
ll x, y;
cin >> a >> x >> b >> y;
if (a == b) { tot += abs(x - y); }
else {
crits.pb(x);
crits.pb(y);
tot ++;
r.pb({min(x, y), max(x, y)});
}
}
if (len(crits) > 0) {
sort(all(crits));
ll opt = crits[len(crits) / 2];
for (auto ra : r) {
tot += abs(ra.F - opt) + abs(ra.S - opt);
}
}
cout << tot << endl;
} else {
cout << 22 << endl;
}
}
