// Improvement - find m using binary search
#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
using namespace std;
int main () {
int k, n;
cin >> k >> n;
char ai, ci;
int bi, di;
long long o = 0;
vector< pair<int, int> > imp;
for (int i=0; i<n; i++) {
cin >> ai >> bi >> ci >> di;
if (ai != ci) {
imp.push_back(make_pair(min(bi, di), max(bi, di)));
} else {
o += abs(bi-di);
}
}
o += imp.size();
if (k == 1) {
vector<int> vals;
for (auto i: imp) {
vals.push_back(i.first);
vals.push_back(i.second);
}
sort(vals.begin(), vals.end());
int mid = vals[vals.size()/2];
for (auto i: vals) {
o += abs(mid-i);
}
cout << o << endl;
return 0;
}
}
