#include "bits/stdc++.h"
using namespace std;
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
//using namespace __gnu_pbds;
//#define ordered_set tree<int, null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update>
//#pragma gcc optimize("O3,unroll-loop")
//#pragma gcc target("sse,sse2,sse3,ssse3,sse4,avx,avx2,fma,abm,mmx,popcnt,tune=native")
#define F first
#define S second
#define rs resize
#define EB emplace_back
#define MP make_pair
#define ALL(v) v.begin(),v.end()
#define siz(v) ((int)v.size())
#define rep(i,n) for(int i=0;i<(n);++i)
#define rep1(i,n) for(int i=1;i<=(n);++i)
#define REP(i,a,b) for(int i=(a);i<=(b);++i)
#ifdef cc12
#define debug(...) cerr<<"#"<<#__VA_ARGS__<<" = ";dbg(__VA_ARGS__);
#define endl '\n'
#define kiyohime ios::sync_with_stdio(false);cin.tie(0);
#else
#define debug(...)
#define kiyohime
#endif
using ll = long long;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
template<typename T> using vec = vector<T>;
template<typename T> using Prior = priority_queue<T>;
template<typename T> using prior = priority_queue<T, vec<T>, greater<T>>;
const int INF = 0x3f3f3f3f;
const ll LLINF = 0x3f3f3f3f3f3f3f3f;
const ll MOD = 1e9 + 7;
//const ll MOD = 998244353;
const double PI = 3.14159265358;
const double EPS = 1e-8;
const int xx[8] = {0,1,0,-1,1,1,-1,-1};
const int yy[8] = {1,0,-1,0,1,-1,-1,1};
unsigned seed = chrono::steady_clock::now().time_since_epoch().count();
mt19937 rng(seed);
uniform_int_distribution<int> dist(1, 1e6);
template<typename T> void dbg(T x){ cerr<<x<<endl; }
template<typename T, typename ...A> void dbg(T x, A ...y){ cerr<<x<<", "; dbg(y...);}
template<typename T> void amax(T &a, T b) {if(a < b) a = b;}
template<typename T> void amin(T &a, T b) {if(a > b) a = b;}
template<typename T> bool INR(T a, T b, T c) {return b <= a && a <= c;}
void pmod(ll &a, ll b) {a = (a+b)%MOD;}
void mmod(ll &a, ll b) {a = (a-b+MOD)%MOD;}
void tmod(ll &a, ll b) {a = (a*b)%MOD;}
template<typename T> void UNI(vec<T> &v) {sort(ALL(v)); v.rs(unique(ALL(v))-v.begin());}
int gi() {int ret; cin >> ret; return ret;}
ll gl() {ll ret; cin >> ret; return ret;}
ll gcd(ll a, ll b) { return b == 0 ? a : gcd(b, a%b);}
ll POW(ll a, ll b) {ll res=1; do{if(b%2)tmod(res,a);tmod(a,a);}while(b>>=1); return res;}
const int MXN = 50;
const int N = MXN + 10;
void solve() {
int n, tp ;
ll sum = 0 ;
vec<pii> g ;
cin >> tp >> n ;
rep(i, n) {
char c1, c2 ;
ll a, b ;
cin >> c1 >> a >> c2 >> b ;
if(c1 == c2) {
sum += abs(a - b) ;
} else {
++sum ;
g.EB(a, b) ;
}
}
int m = siz(g) ;
ll ans = 0 ;
if(tp == 1) {
vec<int> v ;
for(auto i:g) {
v.EB(i.F) ;
v.EB(i.S) ;
}
sort(ALL(v)) ;
rep(i, 2*m) ans += abs(v[i] - v[m]) ;
} else {
sort(ALL(g), [](pii a, pii b) {
return (a.F + a.S) < (b.F + b.S) ;
});
ans = LLINF ;
vec<pii> v ;
rep(i, m) {
v.EB(g.back());
g.pop_back() ;
ll ret = 0 ;
vec<int> tmp ;
for(auto j:v) {
tmp.EB(j.F);
tmp.EB(j.S) ;
}
sort(ALL(tmp)) ;
rep(j, siz(tmp)) ret += abs(tmp[j] - tmp[siz(tmp) / 2]) ;
tmp.clear();
for(auto j:g) {
tmp.EB(j.F) ;
tmp.EB(j.S) ;
}
sort(ALL(tmp)) ;
rep(j, siz(tmp)) ret += abs(tmp[j] - tmp[siz(tmp) / 2]) ;
amin(ans, ret) ;
}
}
cout << ans + sum << endl ;
}
/*
1 5
B 0 A 4
B 1 B 3
A 5 B 7
B 2 A 6
B 1 A 7
2 5
B 0 A 4
B 1 B 3
A 5 B 7
B 2 A 6
B 1 A 7
*/
int32_t main(){
kiyohime
int T = 1;
// cin >> T;
rep1(i, T) {
// cout << "Case #" << i << endl ;
solve();
// cout << endl ;
}
}
// _____ _ ___ ___
// | |___ _ _ ___ _ _ _____| |_ ___ ___|_ | |_ |
// | --| _| | | _| | | | . | -_| _|_| |_| _|
// |_____|___|___|___|___|_|_|_|___|___|_| |_____|___|
