#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define pb push_back
#define all(x) begin(x), end(x)
#define SZ(x) (int)(x).size()
#define cps(x) sort(all(x)), (x).erase(unique(all(x)), end(x))
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int n0 = 1e5 + 123;
int n, k, m, l[n0], r[n0];
ll ans;
int main() {
ios_base::sync_with_stdio(false), cin.tie(NULL);
cin >> k >> n;
for (int i = 0; i < n; i++) {
char c1, c2;
int L, R;
cin >> c1 >> L >> c2 >> R;
if (L > R) swap(L, R);
ans += R - L;
if (c1 != c2) {
l[m] = L, r[m] = R;
m++;
}
}
if (k == 1) {
vector <int> v;
for (int i = 0; i < m; i++)
v.pb(l[i]), v.pb(r[i]);
sort(all(v));
int j = SZ(v) / 2;
for (int i = 0; i < m; i++) {
if (v[j] < l[i]) ans += 2 * (l[i] - v[j]);
if (r[i] < v[j]) ans += 2 * (v[j] - r[i]);
}
}
cout << ans + m;
}
