#include <bits/stdc++.h>
#define ll long long
#define all(x) x.begin(), x.end()
#define Neco "Palembang Bridges"
#define resp(x) sort(all(x)), x.resize(unique(all(x)) - x.begin())
#define getbit(x,i) ((x >> i)&1)
#define _left id * 2, l, mid
#define _right id * 2 + 1, mid + 1, r
#define cntbit(x) __builtin_popcountll(x)
#define fi(i, a, b) for(int i = a; i <= b; i++)
#define fid(i, a, b) for(int i = a; i >= b; i--)
#define maxn (int) 2e5 + 7
using namespace std;
const ll mod = 1e9 + 7; //972663749
const ll base = 911382323;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll GetRandom(ll l, ll r)
{
return uniform_int_distribution<ll> (l, r)(rng);
}
int n, N, k;
ll Sum, pre[maxn], suf[maxn];
ll Sum1, Sum2, ans = 1e18;
multiset<int> S1, S2;
pair<int, int> a[maxn];
void Peko() {
if(S2.size() > S1.size()) {
int val = *S2.begin();
S1.insert(val), S2.erase(S2.begin());
Sum1 -= val, Sum2 -= val;
}
if(S1.size() > S2.size() + 1) {
int val = *S1.rbegin();
S1.erase(prev(S1.end())), S2.insert(val);
Sum1 += val, Sum2 += val;
}
}
void Add(int x) {
int mid = S1.empty() ? 0 : *S1.rbegin();
if(x > mid) S2.insert(x), Sum2 += x;
else S1.insert(x), Sum1 -= x;
Peko();
}
void solve()
{
cin >> k >> n;
fi(i, 1, n) {
char T1, T2; int x, y;
cin >> T1 >> x >> T2 >> y;
if(T1 == T2) Sum += abs(x - y);
else a[++N] = {x, y};
}
sort(a + 1, a + 1 + N, [](pair<int, int> x, pair<int, int> y) { return x.first + x.second < y.first + y.second; } );
fi(i, 1, N) {
Add(a[i].first), Add(a[i].second);
ll mid = *S1.rbegin(), L1 = S1.size(), L2 = S2.size();
pre[i] = mid * L1 - mid * L2 + Sum1 + Sum2;
}
S1.clear(), S2.clear(), Sum1 = Sum2 = 0;
fid(i, N, 1) {
Add(a[i].first), Add(a[i].second);
ll mid = *S1.rbegin(), L1 = S1.size(), L2 = S2.size();
suf[i] = mid * L1 - mid * L2 + Sum1 + Sum2;
}
if(k == 1) ans = Sum + suf[1];
else
{
fi(i, 0, N) ans = min(ans, Sum + pre[i] + suf[i + 1]);
}
cout << ans + N;
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
if(fopen(Neco".inp", "r")) {
freopen(Neco".inp", "r", stdin);
freopen(Neco".out", "w", stdout);
}
int nTest = 1;
// cin >> nTest;
while(nTest--)
{
solve();
}
return 0;
}
