#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}());
const ll mod=1000000007;
const ll mod2=998244353;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head
const int N=101000;
int k,n,m,s[N],t[N],a[N],b[N],p[N];
char ss[N],tt[N];
ll pf[N],sf[N];
struct ds{
int n,m;
ll s;
ds() { n=s=0; }
multiset<int> L,R;
void add(int x,int y) {
if (x>y) swap(x,y);
if (n==0) {
s=y-x;
L.insert(x);
R.insert(y);
n+=2;
m=x;
return;
}
if (x<=m&&y<=m) {
L.insert(x);
L.insert(y);
R.insert(*prev(L.end()));
L.erase(prev(L.end()));
ll diff=m-*L.rbegin();
m=*L.rbegin();
s+=abs(x-m)+abs(y-m);
s+=diff;
} else if (x<=m&&y>m) {
L.insert(x);
R.insert(y);
s+=abs(x-m)+abs(y-m);
} else {
assert(x>m&&y>m);
R.insert(x);
R.insert(y);
L.insert(*R.begin());
R.erase(R.begin());
ll diff=*L.rbegin()-m;
m=*L.rbegin();
s+=abs(x-m)+abs(y-m);
s+=diff;
}
n+=2;
}
};
int main() {
scanf("%d%d",&k,&n);
rep(i,1,n+1) scanf("\n%c %d %c %d",ss+i,s+i,tt+i,t+i);
ll ans=1e18,same=0;
rep(i,1,n+1) {
if (ss[i]==tt[i]) {
same+=abs(s[i]-t[i]);
}
else a[++m]=s[i],b[m]=t[i];
}
rep(i,1,m+1) p[i]=i;
sort(p+1,p+1+m,[&](int i,int j) {
return a[i]+b[i]<a[j]+b[j];
});
ds pref;
rep(i,1,m+1) {
pref.add(a[p[i]],b[p[i]]);
pf[i]=pref.s;
}
ds suff;
per(i,1,m+1) {
suff.add(a[p[i]],b[p[i]]);
sf[i]=suff.s;
}
rep(i,1,m+1) ans=min(ans,pf[i]+sf[i+1]);
if (k==2) printf("%lld",ans+same+m);
else printf("%lld\n",pf[m]+same+m);
}
