#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<vi> vvi;
typedef vector<vll> vvll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<pii> vpii;
typedef vector<pll> vpll;
typedef vector<vpii> vvpii;
typedef vector<vpll> vvpll;
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) (int)(x).size()
#define fi first
#define se second
template<class T> bool ckmin(T &a, const T &b) {return a > b ? a = b, 1 : 0;}
template<class T> bool ckmax(T &a, const T &b) {return a < b ? a = b, 1 : 0;}
namespace debug {
void __print(int x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for(auto z : x) cerr << (f++ ? "," : ""), __print(z); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if(sizeof...(v)) cerr << ", "; _print(v...);}
#ifdef DEBUG
#define dbg(x...) cerr << "\e[91m" << "LINE(" << __LINE__ << ") -> " << "[" << #x << "] = ["; _print(x); cerr << "\033[0m";
#else
#define dbg(x...)
#endif
}
using namespace debug;
const char nl = '\n';
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
void solve() {
int k, n;
cin >> k >> n;
ll ans = 0;
vpll v;
for(int i = 0; i < n; ++i) {
char a, b;
int x, y;
cin >> a >> x >> b >> y;
if(a == b) {
ans += abs(x - y);
} else {
v.pb({x, y});
++ans;
}
}
sort(all(v), [](pll a, pll b) {
return a.fi + a.se < b.fi + b.se;
});
dbg(v);
priority_queue<ll> levi;
priority_queue<ll, vll, greater<>> desni;
ll lsum = 0, rsum = 0;
auto ispisi = [](priority_queue<ll> pq) {
while(sz(pq)) {
dbg(pq.top());
pq.pop();
}
};
auto insert = [&](ll x) {
levi.push(x);
lsum += x;
while(sz(levi) > sz(desni)) {
ll naj = levi.top();
levi.pop();
lsum -= naj;
rsum += naj;
desni.push(naj);
}
while(sz(levi) < sz(desni)) {
ll naj = desni.top();
desni.pop();
rsum -= naj;
lsum += naj;
levi.push(naj);
}
};
auto obrisi = [&]() {
while(sz(levi)) levi.pop();
while(sz(desni)) desni.pop();
lsum = 0;
rsum = 0;
};
n = sz(v);
vll pref(n + 2), suf(n + 2);
for(int i = 1; i <= n; ++i) {
auto p = v[i - 1];
insert(p.fi);
insert(p.se);
pref[i] = rsum - lsum;
}
obrisi();
for(int i = n; i >= 1; --i) {
auto p = v[i - 1];
insert(p.fi);
insert(p.se);
suf[i] = rsum - lsum;
}
dbg(pref);
ll dodaj = 1e18 + 12;
if(k == 2) {
for(int i = 1; i <= n; ++i) {
ckmin(dodaj, pref[i] + suf[i + 1]);
}
} else {
dodaj = pref[n];
}
ans += dodaj;
cout << ans << nl;
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int testCases = 1;
//cin >> testCases;
while(testCases--)
solve();
}
