#include <bits/stdc++.h>
#define int long long
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
using namespace std;
signed main() {
ios_base::sync_with_stdio(false); cin.tie(nullptr);
int n,k; cin >> k >> n;
int sum=0;
vector<int> a;
for (int i = 0; i < n; i++){
char p,q; int s,t; cin >> p >> s >> q >> t;
if(s>t) swap(s,t);
if(p!=q) {
a.push_back(s);
a.push_back(t);
sum++;
}else{
sum+=abs(s-t);
}
}
n=sz(a);
sort(all(a));
if(n==0){
cout << sum << "\n";
return 0;
}
if(k==1){
int med=(a[sz(a)/2]+a[(sz(a)-1)/2])/2;
for (int i = 0; i < sz(a); i++)
{
sum+=max(0LL,abs(a[i]-med));
}
}
cout << sum << "\n";
return 0;
}
