#include<bits/stdc++.h>
using namespace std;
typedef pair<int,int> pii;
typedef vector<pii> vii;
typedef vector<int> vi;
int main(){
int k,n;
cin >> k >> n;
int sol=0;
vii v(0);
for (int i=n;i>0;i--){
char a,b;
int x,y;
cin >> a >> x >> b >> y;
if (a==b){
sol+=abs(x-y);
n--;
}
else v.push_back(pii{x,y});
}
if (k==1){
vi a;
for (pii x:v){
a.push_back(x.first);
a.push_back(x.second);
}
//cerr << v.size() << ' '<< a.size();
int median=v.size();
//auto it=a.begin();
//for (int i=1;i<median;i++) it++;
//nth_element(a.begin(),it,a.end());
//int piv=*it;
sort(a.begin(),a.end());
int piv=a[median];
for (pii x:v){
sol++;
sol+=abs(x.first-piv);
sol+=abs(x.second-piv);
}
cout << sol<<endl;
}
}
