#include <iostream>
#include <fstream>
#include <algorithm>
#include <climits>
using namespace std;
const int nmax=100005;
pair<int,int> v[nmax],a[2*nmax];
long long act,neinc,term,sum_neinc,sum_term,ans,fx;
char wh1,wh2;
int n,i,j,k,p1,p2,cate;
long long abss(long long x)
{
if(x<0) return -x;
return x;
}
void solve_1()
{
for(i=1;i<=cate;i++)
{
a[2*i-1]={v[i].first,-1};
a[2*i]={v[i].second,1};
sum_neinc+=1LL*v[i].first;
}
neinc=cate;
sort(a+1,a+2*cate+1);ans=LLONG_MAX;
for(i=1;i<=2*cate;i++)
{
if(a[i].second==-1)
neinc--,sum_neinc-=1LL*a[i].first;
else term++,sum_term+=1LL*a[i].first;
act=a[i].first;
ans=min(ans,2*(sum_neinc-neinc*act+term*act-sum_term));
}
}
int main()
{
//freopen("data.in","r",stdin);
ios_base::sync_with_stdio(false);
cin>>k>>n;
for(i=1;i<=n;i++)
{
cin>>wh1>>p1>>wh2>>p2;
fx+=(1LL*abss(p2-p1));
if(wh1!=wh2)
{
fx++;
if(p1>p2) swap(p1,p2);
v[++cate]={p1,p2};
}
}
if(k==1)
solve_1();
cout<<fx+ans;
return 0;
}
