#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> PII;
typedef vector<pair<int, int>> VPII;
typedef vector<long long> VL;
#define PB push_back
#define ALL(x) x.begin(), x.end()
#define SPACE ' '
#define LINE '\n'
priority_queue<int> lq;
priority_queue<int, vector<int>, greater<int>> rq;
ll lsum = 0, rsum = 0;
void insert(int x) {
if (lq.empty() || x <= lq.top()) {
lq.push(x);
lsum += x;
} else {
rq.push(x);
rsum += x;
}
if (lq.size() > rq.size() + 1) {
int tmp = lq.top();
lq.pop();
lsum -= tmp;
rq.push(tmp);
rsum += tmp;
} else if (rq.size() > lq.size()) {
int tmp = rq.top();
rq.pop();
rsum -= tmp;
lq.push(tmp);
lsum += tmp;
}
}
void solve() {
int n, k;
cin >> k >> n;
ll same = 0;
VPII vec = {{0, 0}}; // Start with dummy element
for (int i = 0; i < n; ++i) {
char a, b;
int x, y;
cin >> a >> x >> b >> y;
if (a == b) {
same += abs(x - y);
} else {
vec.PB({x, y});
}
}
sort(ALL(vec), [](const PII &a, const PII &b) {
return a.first + a.second < b.first + b.second;
});
n = vec.size() - 1;
VL pref(n + 1, 0);
for (int i = 1; i <= n; ++i) {
auto [x, y] = vec[i];
insert(x);
insert(y);
pref[i] = rsum - lsum;
}
ll ans = pref[n];
if (k == 2) {
while (!lq.empty()) lq.pop();
while (!rq.empty()) rq.pop();
lsum = rsum = 0;
for (int i = n; i >= 1; --i) {
auto [x, y] = vec[i];
insert(x);
insert(y);
ans = min(ans, rsum - lsum + pref[i - 1]);
}
}
cout << same + ans + n << LINE;
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int t = 1;
// cin >> t;
while (t--)
solve();
}
