#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#define ll long long
#define ld long double
#define ull unsigned long long
#define ff first
#define ss second
#define pii pair<int,int>
#define pll pair<long long, long long>
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define rep(i, b) for(int i = 0; i < (b); ++i)
#define rep2(i,a,b) for(int i = a; i <= (b); ++i)
#define rep3(i,a,b,c) for(int i = a; i <= (b); i+=c)
#define count_bits(x) __builtin_popcountll((x))
#define all(x) (x).begin(),(x).end()
#define siz(x) (int)(x).size()
#define forall(it,x) for(auto& it:(x))
using namespace __gnu_pbds;
using namespace std;
typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;
//mt19937 mt;void random_start(){mt.seed(chrono::time_point_cast<chrono::milliseconds>(chrono::high_resolution_clock::now()).time_since_epoch().count());}
//ll los(ll a, ll b) {return a + (mt() % (b-a+1));}
const int INF = 1e9+50;
const ll INF_L = 1e18+40;
const ll MOD = 1e9+7;
struct seg
{
int t,l,r;
ll c;
};
struct node
{
ll l = 0;
ll r = (1LL<<31LL)-1;
pll min_ = {1e18,-1};
node* left = NULL;
node* right = NULL;
void sons()
{
if(left == NULL)
{
left = new node;
left -> l = l;
left -> r = (l+r)/2;
left -> min_ = {1e18,l};
right = new node;
right -> l = (l+r)/2+1;
right -> r = r;
right -> min_ = {1e18,(l+r)/2+1};
}
}
pll get_min(int l2, int r2)
{
if(r < l2 || l > r2) return {1e18,-1};
if(l >= l2 && r <= r2) return min_;
sons();
return min(left->get_min(l2,r2),right->get_min(l2,r2));
}
void set_min(int p, ll x)
{
if(l == r)
{
min_ = {x,l};
return;
}
sons();
if(p <= (l+r)/2) left->set_min(p,x);
else right->set_min(p,x);
min_ = min(left->min_,right->min_);
}
};
vector<seg> segs;
map<int,set<pii>> opt;
node tree_;
ll dist[100001];
int main()
{
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
//random_start();
int m,n;
cin >> m >> n;
rep(i,n)
{
int t,l,r,c;
cin >> t >> l >> r >> c;
segs.pb({t,l,r,c});
opt[l-t+(1<<30)].insert({t+l,i});
dist[i] = 1e18;
}
forall(it,opt) tree_.set_min(it.ff,(*it.ss.begin()).ff);
priority_queue<pll,vector<pll>,greater<pll>> pq;
rep(i,n) if(segs[i].l == 1) pq.push({segs[i].c,i});
while(!pq.empty())
{
pll t = pq.top();
pq.pop();
if(dist[t.ss] != 1e18) continue;
dist[t.ss] = t.ff;
int l = segs[t.ss].r-segs[t.ss].t+1+(1<<30);
int r = segs[t.ss].t+segs[t.ss].r+1;
while(true)
{
pll min_ = tree_.get_min(0,l);
if(min_.ff > r) break;
int ind = (*opt[min_.ss].begin()).ss;
pq.push({t.ff+segs[ind].c,ind});
opt[min_.ss].erase(opt[min_.ss].begin());
if(siz(opt[min_.ss]) == 0) tree_.set_min(min_.ss,1e18);
else tree_.set_min(min_.ss,(*opt[min_.ss].begin()).ff);
}
}
ll ans = 1e18;
rep(i,n) if(segs[i].r == m) ans = min(ans,dist[i]);
if(ans != 1e18) cout << ans << "\n";
else cout << "-1\n";
}
