#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define endl "\n";
#define all(x) x.begin(), x.end()
const ll MOD = 1e9+7;
#define int long long
struct Person {
ll start, end;
bool operator<(const Person& other) const {
return start + end < other.start + other.end;
}
};
struct House {
ll location;
bool isStart;
bool operator<(const House& other) const {
return location < other.location;
}
};
void solve2(int k, int n) {
vector<Person> people;
ll sum = 0;
for (int i = 0; i < n; i++) {
char a, b; int s, e;
cin >> a >> s >> b >> e;
if (a == b) {
sum += abs(e-s);
} else {
if (s > e) {
swap(s, e);
}
people.push_back({s, e});
sum++;
}
}
sort(all(people));
ll minLoss = 0;
multiset<int> lower;
multiset<int> upper;
vector<int> pref(people.size());
ll pos = 0;
ll loss = 0;
for (int i = 0; i < people.size(); i++) {
ll left = lower.size();
ll right = upper.size();
upper.insert(people[i].start);
upper.insert(people[i].end);
while (lower.size() < upper.size()) {
lower.insert(*upper.begin());
upper.erase(upper.begin());
}
ll newPos = *lower.rbegin();
loss -= left * (newPos - pos);
loss += right * (newPos - pos);
loss += abs(newPos - people[i].start) + abs(newPos - people[i].end);
pos = newPos;
pref[i] = loss;
}
lower.clear();
upper.clear();
pos = 0;
loss = 0;
vector<int> suff(people.size());
for (int i = people.size()-1; i >= 0; i--) {
ll left = lower.size();
ll right = upper.size();
upper.insert(people[i].start);
upper.insert(people[i].end);
while (lower.size() < upper.size()) {
lower.insert(*upper.begin());
upper.erase(upper.begin());
}
ll newPos = *lower.rbegin();
loss -= left * (newPos - pos);
loss += right * (newPos - pos);
loss += abs(newPos - people[i].start) + abs(newPos - people[i].end);
pos = newPos;
suff[i] = loss;
}
minLoss = 1e18;
for (int i = 0; i < people.size()-1; i++) {
minLoss = min(minLoss, pref[i] + suff[i+1]);
}
cout << sum + minLoss << endl;
}
void solve() {
int k, n; cin >> k >> n;
if (k == 2) {
solve2(k, n);
return;
}
vector<House> houses;
ll sum = 0;
ll initLoss = 0;
int nonTriv = 0;
for (int i = 0; i < n; i++) {
char a; int s; char b; int e;
cin >> a >> s >> b >> e;
if (a == b) {
sum += abs(e-s);
} else {
nonTriv++;
if (s > e) {
swap(s, e);
}
sum += abs(e-s);
sum++;
initLoss += s;
houses.push_back({s, true});
houses.push_back({e, false});
}
}
sort(all(houses));
ll minLoss = initLoss;
ll curLoss = initLoss;
int left = 0;
int right = nonTriv;
for (int i = 0; i < houses.size(); i++) {
if (i > 0) {
curLoss -= right * (houses[i].location - houses[i-1].location);
curLoss += left * (houses[i].location - houses[i-1].location);
} else {
curLoss -= right * houses[i].location;
}
if (houses[i].isStart) {
right--;
} else {
left++;
}
minLoss = min(minLoss, curLoss);
}
cout << sum + minLoss*2 << endl;
}
signed main() {
ios::sync_with_stdio(0); cin.tie(NULL);
//freopen("example.in", "r", stdin);
// freopen("hayfeast.out", "w", stdout);
int t = 1; // cin >> t;
while (t--) {
solve();
}
}
