//Make CSP great again
//Vengeance
#include <bits/stdc++.h>
#define TASK "TESTCODE"
#define Log2(x) 31 - __builtin_clz(x)
using namespace std;
const int N = 2e5;
int k, n;
long long add, res = 1e18;
set<int> pos;
multiset<pair<int, int> > L, mid, R;
long long sum[3];
map<int, int> comp;
long long t[N + 1];
int cnt[2];
struct FenwickTree
{
long long tree[N + 1];
void add(int pos, int val)
{
for (; pos <= N; pos += (pos & -pos))
{
tree[pos] += val;
}
}
long long sum(int pos)
{
long long ret = 0;
for (; pos > 0; pos -= (pos & -pos))
{
ret += tree[pos];
}
return ret;
}
long long sum(int l, int r)
{
return sum(r) - sum(l - 1);
}
} tree[4];
void read()
{
cin >> k >> n;
while(n--)
{
char P, Q;
int s, t;
cin >> P >> s >> Q >> t;
if (P == Q)
{
add += abs(s - t);
continue;
}
pos.insert(s);
pos.insert(t);
if (s > t)
{
swap(s, t);
}
L.insert({s, t});
//R.insert({t, s});
++cnt[1];
sum[1] += s + t;
++add;
}
}
vector<pair<int, int> > point;
long long Get(int i, int sz)
{
int low = 1, high = N;
while(low <= high)
{
int mid = (low + high)/2;
if (tree[i].sum(mid) >= sz)
{
high = mid - 1;
}
else
{
low = mid + 1;
}
}
long long ret = t[low] * tree[i].sum(low - 1) - tree[i + 1].sum(low - 1) + tree[i + 1].sum(low + 1, N) - tree[i].sum(low + 1, N) * t[low];
assert(ret >= 0);
//cerr << t[low] << ' ' << ret << ' ';
return ret;
}
void solve()
{
if (pos.empty())
{
cout << add;
return ;
}
if (k == 1)
{
for (int x : pos)
{
while(!L.empty() && L.begin()->first <= x)
{
sum[2] += L.begin()->second - L.begin()->first;
--cnt[1];
sum[1] -= L.begin()->first + L.begin()->second;
mid.insert({L.begin()->second, L.begin()->first});
L.erase(L.begin());
}
while(!mid.empty() && mid.begin()->first <= x)
{
++cnt[0];
sum[0] += mid.begin()->first + mid.begin()->second;
sum[2] -= mid.begin()->first - mid.begin()->second;
mid.erase(mid.begin());
}
res = min(res, 2LL * x * cnt[0] - sum[0] + sum[1] - 2LL * cnt[1] * x + sum[2]);
}
cout << res + add;
return ;
}
int j = 0;
for (auto &p : pos)
{
comp[p] = ++j;
t[j] = p;
}
for (auto &p : L)
{
point.emplace_back(p.first, p.second);
tree[2].add(comp[p.first], 1);
tree[2].add(comp[p.second], 1);
tree[3].add(comp[p.first], p.first);
tree[3].add(comp[p.second], p.second);
}
sort(point.begin(), point.end(), [&](auto &x, auto &y)
{
return x.first + x.second < y.first + y.second;
});
for (int i = 0; i < point.size(); ++ i)
{
res = min(res, Get(0, i) + Get(2, point.size() - i));
tree[2].add(comp[point[i].first], -1);
tree[2].add(comp[point[i].second], -1);
tree[3].add(comp[point[i].first], -point[i].first);
tree[3].add(comp[point[i].second], -point[i].second);
tree[0].add(comp[point[i].first], 1);
tree[0].add(comp[point[i].second], 1);
tree[1].add(comp[point[i].first], point[i].first);
tree[1].add(comp[point[i].second], point[i].second);
//cerr << '\n';
}
cout << res + add;
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
if (fopen(TASK".INP", "r"))
{
freopen(TASK".INP", "r", stdin);
//freopen(TASK".OUT", "w", stdout);
}
int t = 1;
bool typetest = false;
if (typetest)
{
cin >> t;
}
for (int __ = 1; __ <= t; ++ __)
{
//cout << "Case " << __ << ": ";
read();
solve();
}
}
