#include <bits/stdc++.h>
#define bit(i, x) (x >> i & 1)
#define ll long long
#define sz(x) (int)(x).size()
const int N = 2e5 + 5;
const int mod = 998244353;
using namespace std;
int k, n;
pair<int, int> a[N];
int m;
ll l[N], r[N];
ll bonus;
struct Median{
multiset<int> l, r;
ll sl = 0, sr = 0;
void init() {
l.clear();
r.clear();
sl = sr = 0;
}
void insert(int x) {
if(l.empty()) {
l.insert(x);
sl += x;
}
else {
int mx_l = *l.rbegin();
if(x <= mx_l) {
l.insert(x);
sl += x;
}
else {
r.insert(x);
sr += x;
}
}
while(sz(l) - sz(r) > 1) {
int top = *l.rbegin();
l.erase(l.find(top));
r.insert(top);
sl -= top;
sr += top;
}
while(sz(r) > sz(l)) {
int top = *r.begin();
r.erase(r.find(top));
l.insert(top);
sr -= top;
sl += top;
}
}
int med() {
return *l.rbegin();
}
ll val() {
int mid = *l.rbegin();
return 1LL * (sz(l) - sz(r)) * mid - (sl - sr);
}
void Print() {
for(auto i : l) cout << i << " ";
cout << "\n";
for(auto i : r) cout << i << " ";
cout << "\n";
}
} M;
mt19937 rng(time(0));
int rnd(int l, int r) {
return rng() % (r - l + 1) + l;
}
signed main(int argc, char* argv[]) {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> k >> n;
for(int i = 1; i <= n; i++) {
char p, q; int s, t;
cin >> p >> s >> q >> t;
if(s > t) swap(s, t);
if(p == q) {
bonus += abs(t - s);
}
else {
bonus++;
a[++m] = {s, t};
}
}
if(k == 2) {
sort(a + 1, a + m + 1, [&](pair<int, int> x, pair<int, int> y) {
return (x.first + x.second < y.first + y.second);
});
for(int i = 1; i <= m; i++) {
M.insert(a[i].first);
M.insert(a[i].second);
l[i] = M.val();
}
M.init();
for(int i = m; i >= 1; i--) {
M.insert(a[i].first);
M.insert(a[i].second);
r[i] = M.val();
}
ll res = LLONG_MAX;
for(int i = 1; i <= m; i++) res = min(res, l[i] + r[i + 1]);
cout << res + bonus;
}
else {
sort(a + 1, a + m + 1, [&](pair<int, int> x, pair<int, int> y) {
return (x.first + x.second < y.first + y.second);
});
for(int i = 1; i <= m; i++) {
M.insert(a[i].first);
M.insert(a[i].second);
l[i] = M.val();
// cout << a[i].first << " " << a[i].second << "\n";
}
// M.Print();
// cout << M.med() << "\n";
cout << l[m] + bonus;
}
return 0 ^ 0;
}
