#include <bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define ll long long
#define PB push_back
#define int long long
#define _sz(e) (int)e.size()
#define pii pair <int , int>
#define _all(e) e.begin() , e.end()
#define FAST ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("sse,sse4,avx,avx2")
const ll maxn = 1e5 + 4 , N = 2e6 + 4 , mod = 1e9 + 7 , INF = 1e18 + 4 , lg = 43;
int n , k , sumL , sumR , sumT , pre[maxn] , suf[maxn];
priority_queue <int> L , R;
vector <pii> vec;
inline bool cmp(pii a , pii b) {
return a.F + a.S < b.F + b.S;
}
void add(int x) {
int med = (_sz(L) ? L.top() : INF);
if(x <= med) L.push(x) , sumL += x;
else R.push(-x) , sumR += x;
if(_sz(L) < _sz(R) - 1) {
int cur = R.top();
R.pop(); L.push(-cur);
sumL += -cur , sumR -= -cur;
}
else if (_sz(L) - 1 > _sz(R)) {
int cur = L.top();
L.pop(); R.push(-cur);
sumR += cur , sumL -= cur;
}
}
int32_t main() {
FAST;
cin >> k >> n;
for (int i = 0; i < n; ++i) {
char a , b; int s , t;
cin >> a >> s >> b >> t;
if(a == b) sumT += abs(s - t);
else vec.PB({s , t});
}
sort(_all(vec) , cmp);
for (int i = 0; i < _sz(vec); ++i) {
add(vec[i].F) , add(vec[i].S);
int med = L.top();
pre[i + 1] = (_sz(L) * med - sumL) + (sumR - _sz(R) * med);
}
while(_sz(L)) L.pop();
while(_sz(R)) R.pop();
sumL = sumR = 0;
for (int i = _sz(vec) - 1; i >= 0; --i) {
add(vec[i].F) , add(vec[i].S);
int med = L.top();
suf[_sz(vec) - i] = (_sz(L) * med - sumL) + (sumR - _sz(R) * med);
}
if(k == 1) {
cout << pre[_sz(vec)] + sumT + _sz(vec) << '\n';
}
else {
int ans = INF;
for (int i = 0; i <= _sz(vec); ++i) {
ans = min(ans , pre[i] + suf[_sz(vec) - i]);
}
cout << ans + sumT + _sz(vec) << '\n';
}
}
