#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
#include <unordered_map>
#include <unordered_set>
#define ll long long
#define ld long double
#define pl pair<ll, ll>
#define vi vector<ll>
#define vii vector<vi>
#define vc vector<char>
#define vcc vector<vc>
#define vp vector<pl>
#define mi map<ll,ll>
#define mc map<char,int>
#define sortx(X) sort(X.begin(),X.end());
#define all(X) X.begin(),X.end()
#define allr(X) X.rbegin(),X.rend()
#define ln '\n'
#define YES {cout << "YES\n"; return;}
#define NO {cout << "NO\n"; return;}
#define MUN {cout << "-1\n"; return;}
const int MODE = 1e9 + 7;
using namespace std;
vector<ll> getMedian(vector<pair<ll, pl>> &X)
{
priority_queue<ll> L;
priority_queue<ll, vector<ll>, greater<ll>> R;
ll l = 0, r = 0;
vector<ll> res;
for (auto [mid, p] : X)
{
vi NUM = {p.first, p.second};
for (auto x : NUM) {
if (!L.empty() && x > L.top()) {
R.push(x);
r+=x;
}
else {
L.push(x);
l += x;
}
while (L.size() > R.size() + 1)
{
l -= L.top(); r += L.top();
R.push(L.top());
L.pop();
}
while (R.size() > L.size())
{
r -= R.top(); l += R.top();
L.push(R.top());
R.pop();
}
}
ll med = L.top();
ll re = med * L.size() - l;
re += r - med * R.size();
res.push_back(re);
}
return (res);
}
void solve(int tc) {
ll n, k;
cin >> k >> n;
ll sol = 0;
vp X;
for (int i = 0; i < n; i++)
{
char c1, c2; ll a, b;
cin >> c1 >> a >> c2 >> b;
if (a>b) swap(a, b);
if (c1 == c2) sol += abs(a - b);
else X.push_back({a, b});
}
n = X.size();
vector<pair<ll, pl>> Y;
for (int i = 0; i < n; i++)
Y.push_back({X[i].first+X[i].second, X[i]});
sortx(Y);
vi L = getMedian(Y);
ll mn = INT64_MAX;
if (L.empty()) mn = 0;
else {
if (k == 1) mn = L.back();
else {
reverse(all(Y));
vi R = getMedian(Y);
reverse(all(R));
for (int i = 0; i < R.size()-1; i++)
mn = min(mn, L[i] + R[i + 1]);
}
}
sol += mn + Y.size();
cout << sol << '\n';
}
int main()
{
ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
int size = 1;
// freopen("248.in", "r", stdin);
// freopen("248.out", "w", stdout);
// cin >> size;
for (int i = 1; i <= size; i++)
solve(i);
}
