#include <bits/stdc++.h>
#define tt cin.tie(0), cout.tie(0), ios_base::sync_with_stdio(0)
#define fo freopen((NAME+".INP").c_str(), "r", stdin), freopen((NAME+".OUT").c_str(), "w", stdout)
#define ll long long
#define ull unsigned long long
#define i128 __int128
#define db long double
#define sz(a) ((int)(a).size())
#define pb emplace_back
#define pf emplace_front
#define pob pop_back
#define pof pop_front
#define lb lower_bound
#define ub upper_bound
#define fi first
#define se second
#define ins emplace
#define mp make_pair
using namespace std;
const int MOD = 1e9+7, MAXN = 1e5+5;
const string NAME = "";
struct Project{
int t,l,r,cost;
}a[MAXN];
int n,m,t[MAXN],sgt[2][MAXN<<2];
ll dp[MAXN],rs=1e18;
vector<int> v;
priority_queue<pair<ll,int>, vector<pair<ll,int>>, greater<pair<ll,int>>> pq;
multiset<pair<int,int>> ms[2][MAXN];
bool check(int i, int j){
if(a[i].t>=a[j].t) return a[i].r-a[i].t+1>=a[j].l-a[j].t;
return a[i].r+a[i].t+1>=a[j].l+a[j].t;
}
void build(int id, int l, int r, int pos, int val){
if(pos<l||r<pos) return;
if(l==r){
ms[0][l].ins(a[val].l-a[val].t,val), ms[1][l].ins(a[val].l+a[val].t,val);
sgt[0][id]=ms[0][l].begin()->fi, sgt[1][id]=ms[1][l].begin()->fi;
return;
}
int mid=(l+r)>>1;
if(pos<=mid) build(id<<1,l,mid,pos,val);
else build(id<<1|1,mid+1,r,pos,val);
sgt[0][id]=min(sgt[0][id<<1],sgt[0][id<<1|1]);
sgt[1][id]=min(sgt[1][id<<1],sgt[1][id<<1|1]);
}
void update(bool type, int id, int l, int r, int u, int v, ll val, int checkval){
if(v<l||r<u||sgt[type][id]>checkval) return;
if(l==r){
while(!ms[type][l].empty()){
pair<int,int> p = *ms[type][l].begin();
if(checkval>=p.fi){
if(dp[p.se]>val+a[p.se].cost) dp[p.se]=val+a[p.se].cost, pq.ins(dp[p.se],p.se);
}else break;
ms[type][l].erase(ms[type][l].begin());
}
if(ms[type][l].empty()) sgt[type][id]=2e9;
else sgt[type][id]=ms[type][l].begin()->fi;
return;
}
int mid=(l+r)>>1;
update(type,id<<1,l,mid,u,v,val,checkval);
update(type,id<<1|1,mid+1,r,u,v,val,checkval);
sgt[type][id]=min(sgt[type][id<<1],sgt[type][id<<1|1]);
}
int main()
{
tt;
if(fopen((NAME + ".INP").c_str(), "r")) fo;
memset(dp,0x3f,sizeof(dp));
memset(sgt,0x3f,sizeof(sgt));
cin >> n >> m;
for(int i = 1; i<=m; ++i){
cin >> a[i].t >> a[i].l >> a[i].r >> a[i].cost;
if(a[i].l==1) dp[i]=a[i].cost, pq.ins(a[i].cost,i);
v.pb(a[i].t);
}
sort(v.begin(),v.end());
v.resize(unique(v.begin(),v.end())-v.begin());
for(int i = 1; i<=m; ++i){
t[i]=lb(v.begin(),v.end(),a[i].t)-v.begin()+1;
build(1,1,sz(v),t[i],i);
}
while(!pq.empty()){
pair<ll,int> top=pq.top();
pq.pop();
if(top.fi>dp[top.se]) continue;
if(a[top.se].r==n) rs=min(rs,top.fi);
update(0,1,1,sz(v),1,t[top.se],top.fi,a[top.se].r-a[top.se].t+1);
update(1,1,1,sz(v),t[top.se]+1,sz(v),top.fi,a[top.se].r+a[top.se].t+1);
}
cout << (rs>=1e18 ? -1 : rs);
}
