#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>
#include <vector>
#include <utility>
using namespace std;
typedef pair<int,int> pi;
typedef long long lint;
int n,k;
vector<pi> sol;
lint solve(){
if(sol.empty()) return 0;
vector<int> ret;
for(auto i : sol){
ret.push_back(i.first);
ret.push_back(i.second);
}
sort(ret.begin(),ret.end());
int med = ret[ret.size()/2];
lint res = 0;
for(auto i : ret){
lint t = i;
t -= med;
res += max(t,-t);
}
return res;
}
bool cmp(pi a, pi b){
return a.first + a.second < b.first + b.second;
}
vector<int> cand;
struct bit{
lint tree[200005];
int piv;
void init(int n){
piv = n+2;
memset(tree,0,sizeof(tree));
}
void add(int x, int v){
x += 2;
while(x <= piv){
tree[x] += v;
x += x & -x;
}
}
int kth(int k){
int p = 0;
for(int i=17; i>=0; i--){
if((p|1<<i) <= piv && tree[p|(1<<i)] < k){
p |= 1<<i;
k -= tree[p];
}
}
return p-1;
}
lint sum(int x){
x += 2;
lint ret = 0;
while(x){
ret += tree[x];
x -= x & -x;
}
return ret;
}
lint sum_range(int s, int e){
return sum(e) - sum(s-1);
}
}bit1, bit2;
lint dp1[100005], dp2[100005];
lint solve2(){
if(sol.empty()) return 0;
sort(sol.begin(), sol.end(), cmp);
for (auto &i : sol){
cand.push_back(i.first);
cand.push_back(i.second);
}
sort(cand.begin(), cand.end());
cand.resize(unique(cand.begin(),cand.end()) - cand.begin());
for (auto &i : sol){
i.first = (int)(lower_bound(cand.begin(),cand.end(),i.first) - cand.begin());
i.second = (int)(lower_bound(cand.begin(),cand.end(),i.second) - cand.begin());
}
bit1.init((int)cand.size());
bit2.init((int)cand.size());
for (int i=0; i<sol.size(); i++){
pi t = sol[i];
bit1.add(t.first,1);
bit1.add(t.second,1);
bit2.add(t.first,cand[t.first]);
bit2.add(t.second,cand[t.second]);
int piv = bit1.kth(i+1);
dp1[i] += bit2.sum_range(piv+1,(int)cand.size()-1);
dp1[i] -= bit1.sum_range(piv+1,(int)cand.size()-1) * cand[piv];
dp1[i] += bit1.sum_range(0,piv-1) * cand[piv];
dp1[i] -= bit2.sum_range(0,piv-1);
}
bit1.init((int)cand.size());
bit2.init((int)cand.size());
for (int i=(int)sol.size()-1; i>=0; i--) {
pi t = sol[i];
bit1.add(t.first,1);
bit1.add(t.second,1);
bit2.add(t.first,cand[t.first]);
bit2.add(t.second,cand[t.second]);
int piv = bit1.kth((int)sol.size()-i);
dp2[i] += bit2.sum_range(piv+1,(int)cand.size()-1);
dp2[i] -= bit1.sum_range(piv+1,(int)cand.size()-1) * cand[piv];
dp2[i] += bit1.sum_range(0,piv-1) * cand[piv];
dp2[i] -= bit2.sum_range(0,piv-1);
}
lint ans = 1e18;
for (int i=0; i<=sol.size(); i++) {
ans = min(ans,(i ? dp1[i-1] : 0) + dp2[i]);
}
return ans;
}
int main(){
lint ret = 0;
scanf("%d %d",&k,&n);
for(int i=0; i<n; i++){
char s1[5], s2[5];
int t,u;
scanf("%s %d %s %d",s1,&t,s2,&u);
if(t > u) swap(t,u);
if(s1[0] != s2[0]){
sol.push_back(pi(t,u));
}
else{
ret += u - t - 1;
}
}
ret += n;
if(k == 1) ret += solve();
else ret += solve2();
printf("%lld",ret);
}
