#include<bits/stdc++.h>
using namespace std;
void speed()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
}
typedef long long llong;
const int MAXN = 1e5 + 10;
const int INF = 1e9 + 10;
struct Person
{
int s, t;
Person(){};
Person(int s, int t)
{
this->s = s;
this->t = t;
}
friend bool operator<(const Person &p1, const Person &p2)
{
return (p1.s + p1.t) < (p2.s + p2.t);
}
};
llong same;
vector < Person > v;
int n, k;
char p[MAXN];
int s[MAXN];
char q[MAXN];
int t[MAXN];
multiset < int > lhalf, rhalf;
llong pref[MAXN];
llong suff[MAXN];
llong lhalfsum;
llong rhalfsum;
void read()
{
cin >> k >> n;
for(int i = 1; i <= n; i++)
{
cin >> p[i] >> s[i] >> q[i] >> t[i];
if(p[i] == q[i])
{
same += abs(t[i] - s[i]);
}
else
{
v.push_back(Person(s[i], t[i]));
}
}
sort(v.begin(), v.end());
n = v.size();
}
void add(int val)
{
int median;
if(lhalf.empty())
median = INF;
else
median = *lhalf.rbegin();
if(val <= median)
{
lhalf.insert(val);
lhalfsum += val;
}
else
{
rhalf.insert(val);
rhalfsum += val;
}
if((int)rhalf.size() - (int)lhalf.size() > 1)
{
auto it = rhalf.begin();
int trans = *it;
rhalf.erase(it);
rhalfsum -= trans;
lhalf.insert(trans);
lhalfsum += trans;
}
else if((int)lhalf.size() - (int)rhalf.size() > 1)
{
auto it = prev(lhalf.end());
int trans = *it;
lhalf.erase(it);
lhalfsum -= trans;
rhalf.insert(trans);
rhalfsum += trans;
}
}
void find_pref()
{
lhalf.clear();
rhalf.clear();
lhalfsum = rhalfsum = 0;
for(int i = 1; i <= n; i++)
{
add(v[i - 1].s);
add(v[i - 1].t);
pref[i] = rhalfsum - lhalfsum;
}
}
void find_suff()
{
lhalf.clear();
rhalf.clear();
lhalfsum = rhalfsum = 0;
for(int i = n; i >= 1; i--)
{
add(v[i - 1].s);
add(v[i - 1].t);
suff[i] = rhalfsum - lhalfsum;
}
}
void solve_k1()
{
cout << (same + pref[n] + n) << endl;
}
void solve_k2()
{
llong ans = pref[n];
for(int i = 1; i <= n; i++)
{
ans = min(ans, pref[i] + suff[i + 1]);
}
cout << (same + ans + n) << endl;
}
void solve()
{
if(k == 1)
solve_k1();
else
solve_k2();
}
int main()
{
speed();
read();
find_pref();
find_suff();
solve();
return 0;
}
/**
1 5
B 0 A 4
B 1 B 3
A 5 B 7
B 2 A 6
B 1 A 7
*/
