#include<bits/stdc++.h>
#define lf double
#define ll long long
#define cc pair<char,char>
#define ull unsigned ll
#define ii pair<int,int>
#define li pair<ll,int>
#define iii pair<int,ii>
#define iiii pair<ii,ii>
#define iiii2 pair<int,iii>
#define lii pair<ll,ii>
#define lolo pair<ll,ll>
#define heap priority_queue
#define mp make_pair
#define st first
#define nd second
#define pb push_back
#define pf push_front
#define ppb pop_back
#define ppf pop_front
#define all(x) x.begin(),x.end()
#define len(x) strlen(x)
#define sz(x) (int) x.size()
#define orta ((bas+son)/2)
#define min3(x,y,z) min(min(x,y),z)
#define max3(x,y,z) max(max(x,y),z)
#define umin(x,y) x=min(x,y)
#define umax(x,y) x=max(x,y)
#define dbgs(x) cerr<<(#x)<<" --> "<<(x)<<" "
#define dbg(x) cerr<<(#x)<<" --> "<<(x)<<endl;getchar()
#define MOD 998244353
#define inf 1000000000000000000
#define M 10000002
#define N 100005
#define LOG 40
#define magic 100
#define KOK 250
#define EPS 0.0025
#define pw(x) ((1ll)<<(x))
#define PI 3.1415926535
using namespace std;
int sz,n,k,x1,x2;
ll ans=inf,pre[N],suf[N],Sum[N*8],add;
int Ok[N*8],tut[N*2];
vector<ii> seg;
char c1,c2;
void clear() {
memset(Sum,0,sizeof(Sum));
memset(Ok,0,sizeof(Ok));
}
ll getsum(int node,int bas,int son,int x,int y) {
if(bas>y || son<x) return 0;
if(bas>=x && son<=y) return Sum[node];
return getsum(node*2,bas,orta,x,y)+getsum(node*2+1,orta+1,son,x,y);
}
int getkth(int node,int bas,int son,int k) {
if(bas==son) return bas;
if(Ok[node*2]>=k) return getkth(node*2,bas,orta,k);
return getkth(node*2+1,orta+1,son,k-Ok[node*2]);
}
void up(int node,int bas,int son,int x) {
if(bas>x || son<x) return ;
if(bas==x && son==x) {
Sum[node]=tut[bas];
Ok[node]=1;
return ;
}
up(node*2,bas,orta,x);
up(node*2+1,orta+1,son,x);
Sum[node]=Sum[node*2]+Sum[node*2+1];
Ok[node]=Ok[node*2]+Ok[node*2+1];
}
void compress() {
vector<iii> v;
for(int i=0;i<sz;i++) {
v.pb({seg[i].st,{i,0}});
v.pb({seg[i].nd,{i,1}});
}
sort(all(v));
for(int i=0;i<2*sz;i++) {
tut[i+1]=v[i].st;
if(v[i].nd.nd) {
seg[v[i].nd.st].nd=i+1;
}
else {
seg[v[i].nd.st].st=i+1;
}
}
}
int main() {
#if 0
freopen("input.txt","r",stdin);
#endif
scanf("%d %d",&k,&n);
for(int i=1;i<=n;i++) {
scanf(" %c %d %c %d",&c1,&x1,&c2,&x2);
if(c1==c2) add+=abs(x1-x2);
else {
if(x1>x2) swap(x1,x2);
seg.pb({x1,x2});
}
}
sort(all(seg),[](ii x,ii y) {
return x.st+x.nd<y.st+y.nd;
});
sz=sz(seg);
compress();
for(int i=0;i<sz;i++) {
up(1,1,2*sz,seg[i].st);
up(1,1,2*sz,seg[i].nd);
int plc=getkth(1,1,2*sz,i+1);
ll dec=getsum(1,1,2*sz,1,plc);
ll add=getsum(1,1,2*sz,plc+1,2*sz);
pre[i+1]=add-dec;
}
clear();
reverse(all(seg));
for(int i=0;i<sz;i++) {
up(1,1,2*sz,seg[i].st);
up(1,1,2*sz,seg[i].nd);
int plc=getkth(1,1,2*sz,i+1);
ll dec=getsum(1,1,2*sz,1,plc);
ll add=getsum(1,1,2*sz,plc+1,2*sz);
suf[i+1]=add-dec;
}
if(k==2) {
for(int i=1;i<=sz;i++) {
umin(ans,pre[i]+suf[sz-i]);
}
}
else {
ans=pre[sz];
}
if(sz==0) ans=0;
printf("%lld",add+ans+sz);
}
