#include <bits/stdc++.h>
#define ld long double
#define endl "\n"
#define fastio ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define pb(x) push_back(x)
#define mp(a,b) make_pair(a,b)
#define ms(v,x) memset(v,x,sizeof(v))
#define all(v) v.begin(),v.end()
#define ff first
#define ss second
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define per(i, a, b) for(int i = b-1; i>=a ; i--)
#define trav(a, x) for(auto& a : x)
#define allin(a , x) for(auto a : x)
#define td(v) v.begin(),v.end()
#define sz(v) (int)v.size()
#define int long long
using namespace std;
typedef vector<int> vi;
#define y1 abacaba
#define left sefude
#define db(x) cerr << #x <<" == "<<x << endl;
#define db2(x,y) cerr<<#x <<" == "<<x<<", "<<#y<<" == "<<y<<endl;
typedef long long ll;
typedef pair<int,int> pii;
inline ll mod(ll n, ll m ){ ll ret = n%m; if(ret < 0) ret += m; return ret; }
ll gcd(ll a, ll b){return (b == 0LL ? a : gcd(b, a%b));}
ll exp(ll a,ll b,ll m){
if(b==0LL) return 1LL;
if(b==1LL) return mod(a,m);
ll k = mod(exp(a,b/2,m),m);
if(b&1LL){
return mod(a*mod(k*k,m),m);
}
else return mod(k*k,m);
}
struct BIT{
int n;
int MAX;
vector<ll> bit;
BIT(){}
BIT(int _n){
n = _n;
MAX = n +2;
bit.resize(n+10,0);
}
ll query(int x){
ll r=0;
while(x>0){
r+=bit[x];
x-=(x&-x);
}
return r;
}
ll query(int l,int r){
if(l > r){
return 0;
}
assert(l<=r);
return query(r) - query(l-1);
}
void update(int x,ll val){
while(x<MAX){
bit[x]+=val;
x+=(x&-x);
}
}
ll find_kth(ll k){
ll sum=0;
ll pos=0;
// 20 == log -> trocar conforme necessario
for(int i=20;i>=0;i--){
if(pos+(1LL<<i)>n)continue;
int atual = bit[pos+(1LL<<i)];
if(sum+atual<k){
sum+=atual;
pos+=(1LL<<i);
}
}
//acha a maior pos com <k;
return pos+1;
}
};
vi comp;
struct mediana{
int n;
int tot;
BIT freq,sum;
mediana(){}
mediana(int n,int tot):n(n),tot(tot){
freq = sum = BIT(n+n);
}
void insert(int x){
int pos = lower_bound(all(comp),x) - comp.begin() + 1;
tot++;
freq.update(pos,1);sum.update(pos,x);
}
ll f(){
int pos = freq.find_kth(tot/2);
ll val = comp[pos-1];
ll r = freq.query(pos) * val - sum.query(pos);
r+= sum.query(pos + 1,n + n) - freq.query(pos+1,n+n) * val;
return r;
}
void clear(){
tot=0;
freq = sum = BIT(n+n);
}
};
const int N = 100100;
int S[N],T[N];
char P[N],Q[N];
int pre[N],suf[N];
int32_t main(){
fastio;
int k,n;
cin >> k >> n;
vector<pii> vec;
ll bef=0;
for(int i=1;i<=n;i++){
cin >> P[i] >> S[i] >> Q[i] >> T[i];
if(S[i] > T[i])swap(S[i],T[i]);
if(P[i] == Q[i]){
bef+=T[i] - S[i];
}else{
bef++;
vec.pb(pii(S[i],T[i]));
comp.pb(S[i]);comp.pb(T[i]);
}
}
sort(all(comp));
comp.erase(unique(all(comp)),comp.end());
sort(all(vec),[&](pii a,pii b){
return a.ff + a.ss < b.ff + b.ss;
});
int tam = sz(vec);
if(tam == 0){
cout << bef << endl;
return 0;
}
mediana Med(n,0);
for(int i=0;i<tam;i++){
Med.insert(vec[i].ff);Med.insert(vec[i].ss);
pre[i] = Med.f();
}
Med.clear();
for(int i = tam-1;i>=0;i--){
Med.insert(vec[i].ff);Med.insert(vec[i].ss);
suf[i] = Med.f();
}
ll ans = pre[tam-1];
if(k == 2){
for(int i=0;i<tam-1;i++){
ans = min(ans,pre[i] + suf[i+1]);
}
}
cout << ans + bef << endl;
// math -> gcd it all
// Did u check N=1? Did you switch N,M?
}
