#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define ff first
#define ss second
#define all(s) s.begin(),s.end()
#define rall(s) s.rbegin(),s.rend()
priority_queue<ll>L;
priority_queue<ll,vector<ll>,greater<ll>>R;
ll sumL=0,sumR=0;
void add(ll x){
ll med=(L.empty()?(ll)1e9:L.top());
if(x<=med){
L.push(x);
sumL+=x;
}
else{
R.push(x);
sumR+=x;
}
if(L.size()<R.size()){
ll y=R.top();
R.pop();
L.push(y);
sumL+=y;
sumR-=y;
}
else if(L.size()>R.size()+1){
ll y=L.top();
L.pop();
R.push(y);
sumR+=y;
sumL-=y;
}
}
int main(){
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
ll K,n;
cin>>K>>n;
vector<array<ll,3>>v;
ll same=0;
for(ll i=1;i<=n;i++){
char p,q;
ll a,b;
cin>>p>>a>>q>>b;
if(p==q){
same+=abs(a-b);
}
else{
v.pb({a+b,a,b});
}
}
sort(all(v));
ll ans=0;
ll m=v.size();
ll pre[m+5],suf[m+5];
pre[0]=0;
for(ll i=0;i<m;i++){
add(v[i][1]);
add(v[i][2]);
pre[i+1]=sumR-sumL;
}
ans=pre[m];
if(K==2){
while(!L.empty()) L.pop();
while(!R.empty()) R.pop();
sumL=sumR=0;
// L.clear();
// R.clear();
suf[m]=0;
for(ll i=m-1;i>=1;i--){
add(v[i][1]);
add(v[i][2]);
suf[i]=sumR-sumL;
ans=min(ans,pre[i]+suf[i]);
}
}
cout<<ans+same+m;
}
