#include <bits/stdc++.h>
#define int long long
using namespace std;
string to_string(string s) { return s; }
template <typename T> string to_string(T v) {
bool first = true;
string res = "[";
for (const auto &x : v) {
if (!first)
res += ", ";
first = false;
res += to_string(x);
}
res += "]";
return res;
}
void dbg_out() { cout << endl; }
template <typename Head, typename... Tail> void dbg_out(Head H, Tail... T) {
cout << ' ' << to_string(H);
dbg_out(T...);
}
#ifdef DEBUG
#define dbg(...) cout << "(" << #__VA_ARGS__ << "):", dbg_out(__VA_ARGS__)
#else
#define dbg(...)
#endif
signed main(void) {
ios_base::sync_with_stdio(false);
cin.tie(0);
int K, N;
cin >> K >> N;
if (K == 1) {
vector<pair<int, int>> intervals;
int sol = 0;
for (int i = 0; i < N; ++i) {
char c, d;
int a, b;
cin >> c >> a >> d >> b;
if (a > b)
swap(a, b);
sol += b - a;
if (c == d)
continue;
intervals.emplace_back(a, b);
}
vector<int> as, bs, vals;
for (auto [a, b] : intervals) {
as.push_back(a);
bs.push_back(b);
vals.push_back(a);
vals.push_back(b);
}
sort(as.begin(), as.end());
sort(bs.begin(), bs.end());
sort(vals.begin(), vals.end());
vals.resize(unique(vals.begin(), vals.end()) - vals.begin());
int best = 1e18;
int cntBefore = 0, sumBefore = 0;
int posB = 0;
int cntAfter = intervals.size();
int sumAfter = accumulate(as.begin(), as.end(), 0LL);
int posA = 0;
int nbInt = intervals.size();
dbg(bs);
for (int x : vals) {
while (posB < nbInt and bs[posB] < x) {
sumBefore += bs[posB++];
cntBefore++;
}
while (posA < nbInt and as[posA] < x) {
sumAfter -= as[posA++];
cntAfter--;
}
int cur = sumAfter - x * cntAfter;
cur += x * cntBefore - sumBefore;
dbg(x, cntBefore, cntAfter, cur);
best = min(best, cur);
}
if (nbInt == 0)
best = 0;
dbg(best, sol);
cout << 2 * best + sol + nbInt << endl;
} else {
}
}
