#include <bits/stdc++.h>
#define int long long
using namespace std;
typedef long long ll;
typedef long double ld;
struct triple {
int a, b, c;
bool operator <(const triple &other) const {
return a < other.a;
}
};
struct median {
multiset <int> a, b;
ll sa, sb;
void push(int x) {
if (b.empty() || x >= *b.begin()) {
b.insert(x);
sb += x;
}
else {
a.insert(x);
sa += x;
}
while (a.size() > b.size()) {
int c = *a.rbegin();
sa -= c;
sb += c;
a.erase(--a.end());
b.insert(c);
}
while (b.size() > a.size() + 1) {
int c = *b.begin();
sb -= c;
sa += c;
b.erase(b.begin());
a.insert(c);
}
}
ll get() {
int m = *b.begin();
return (ll)m * a.size() - sa + sb - (ll)m * b.size();
}
median() {
sa = sb = 0;
}
};
signed main() {
ios_base::sync_with_stdio(false); cin.tie(0); cout.setf(ios::fixed); cout.precision(20);
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
int k, n;
cin >> k >> n;
if (k == 1) {
ll res = 0;
vector <int> a;
for (int i = 0; i < n; ++i) {
char p, q;
int x, y;
cin >> p >> x >> q >> y;
if (p != q) {
++res;
a.push_back(x);
a.push_back(y);
}
else res += abs(x - y);
}
sort(a.begin(), a.end());
int x = a[(int)a.size() / 2];
for (auto y : a) res += abs(x - y);
cout << res << '\n';
}
else {
ll res = 0;
vector <triple> a;
for (int i = 0; i < n; ++i) {
char p, q;
int x, y;
cin >> p >> x >> q >> y;
if (p != q) {
++res;
a.push_back({x + y, x, y});
}
else res += abs(x - y);
}
sort(a.begin(), a.end());
int m = a.size();
vector <ll> f(m + 1), s(m + 1);
median P;
for (int i = 0; i < m; ++i) {
P.push(a[i].b);
P.push(a[i].c);
f[i + 1] = P.get();
}
median S;
for (int i = m - 1; i >= 0; --i) {
S.push(a[i].b);
S.push(a[i].c);
s[i] = S.get();
}
ll ans = 1e18;
for (int i = 0; i < m + 1; ++i) ans = min(ans, res + f[i] + s[i]);
cout << ans << '\n';
}
}
