#include<bits/stdc++.h>
using namespace std;
#define int long long
const int maxn = 1e5 + 5;
int dist[maxn], ptr[4 * maxn];
vector<int> st[4 * maxn];
struct Project {
int t, l, r, c, x, y;
};
vector<Project> prro;
void build(int id, int l, int r){
if(l == r){
st[id].push_back(l);
return;
}
int mid = (l + r) / 2, i = 0, j = 0;
build(2 * id, l, mid);
build(2 * id + 1, mid + 1, r);
while(i < st[2 * id].size() && j < st[2 * id + 1].size()){
if(prro[st[2 * id][i]].y < prro[st[2 * id + 1][j]].y) st[id].push_back(st[2 * id][i++]);
else st[id].push_back(st[2 * id + 1][j++]);
}
while(i < st[2 * id].size()) st[id].push_back(st[2 * id][i++]);
while(j < st[2 * id + 1].size()) st[id].push_back(st[2 * id + 1][j++]);
}
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq;
void update(int id, int l, int r, int boundx, int boundy, int cost){
if(prro[l].x > boundx) return;
if(prro[r].x <= boundx){
while(ptr[id] < st[id].size()){
int v = st[id][ptr[id]];
if(prro[v].y <= boundy){
if(dist[v] > cost + prro[v].c){
dist[v] = cost + prro[v].c;
pq.push({dist[v], v});
}
ptr[id]++;
}else break;
}
return;
}
int mid = (l + r) / 2;
update(id * 2, l, mid, boundx, boundy, cost);
update(id * 2 + 1, mid + 1, r, boundx, boundy, cost);
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
int n, m; cin >> n >> m;
prro.resize(m);
for(int i = 0; i < m; i++){
cin >> prro[i].t >> prro[i].l >> prro[i].r >> prro[i].c;
prro[i].r += 1;
prro[i].x = prro[i].l - prro[i].t;
prro[i].y = prro[i].l + prro[i].t;
}
sort(prro.begin(), prro.end(), [](Project a, Project b){
return a.x < b.x;
});
build(1, 0, m - 1);
for(int i = 0; i < m; i++){
if(prro[i].l == 1){
dist[i] = prro[i].c;
pq.push({dist[i], i});
}else dist[i] = 1e18;
}
while(pq.size()){
auto [cur, u] = pq.top();
pq.pop();
if(cur > dist[u]) continue;
if(prro[u].r >= n + 1){
cout << cur;
return 0;
}
update(1, 0, m - 1, prro[u].r - prro[u].t, prro[u].r + prro[u].t, cur);
}
cout << -1;
}
