#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
priority_queue<ll> lt; // we will need to pop the maximum
priority_queue<ll,vector<ll>,greater<ll>> rt;
ll med=0,lsm=0,rsm=0;
void add(int x)
{
if(med==-1)
{
med=x;
return;
}
if(x<=med)
{
lt.push(x);
lsm+=x;
}
else
{
rt.push(x);
rsm+=x;
}
if(lt.size()+1 < rt.size())
{
// right has more elements
ll y=rt.top();
rt.pop();
rsm-=y;
swap(y,med);
lsm+=y;
lt.push(y);
}
if(rt.size()+1 < lt.size())
{
ll y=lt.top();
lt.pop();
lsm-=y;
swap(y,med);
rsm+=y;
rt.push(y);
}
// x+1 x
// x x
// x+1 x-1
}
long long getsum()
{
return 1ll*lt.size()*med - lsm + rsm - 1ll*rt.size()*med;
}
int main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int k,n;
cin>>k>>n;
ll ans=0;
vector<ll> tp;
pair<ll,ll> b[n+1]={};
vector<pair<ll,ll>> a;
for(int i=0;i<n;i++)
{
char c,p;
int x,y;
cin>>c>>x>>p>>y;
if(x>y)swap(x,y);
if(c==p)
{
ans+=y-x;
}
else
{
ans+=1;
tp.pb(x);
tp.pb(y);
b[i].first=x;
b[i].second=y;
a.pb({x+y,i});
}
}
int sz=tp.size();
if(!sz)
{
cout<<ans<<endl;
return 0;
}
sort(begin(tp),end(tp));
sort(begin(a),end(a));
if(k==1)
{
for(auto i:tp)
{
ans+=abs(tp[sz/2]-i);
}
cout<<ans<<endl;
return 0;
}
sz=a.size();
vector<long long> pre(sz+1);
for(int i=0;i<sz;i++)
{
add(b[a[i].second].first);
add(b[a[i].second].second);
pre[i+1]=getsum();
}
med=-1;
lsm=0,rsm=0;
while(lt.size())lt.pop();
while(rt.size())rt.pop();
ll mi=1e18;
for(int i=sz-1;i>=0;i--)
{
add(b[a[i].second].first);
add(b[a[i].second].second);
mi=min(mi,getsum()+pre[i]);
}
cout<<ans+mi<<endl;
}
