#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef __int128 lll;
typedef long double ld;
typedef pair<ll, ll> pll;
typedef pair<ld, ld> pld;
#define MAX 9223372036854775807LL
#define MIN -9223372036854775807LL
#define INF 0x3f3f3f3f3f3f3f3f
#define fi first
#define se second
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); cout << fixed; cout.precision(10);
#define sp << " "
#define en << "\n"
#define compress(v) sort(v.begin(), v.end()), v.erase(unique(v.begin(), v.end()), v.end())
struct gujo
{
ll T, L, R, C;
};
ll n, m;
gujo a[100010];
vector<pll> vec[100010];
ll dist[100010];
ll ans;
void dijkstra(void)
{
priority_queue<pll> pq;
for(ll i = 1 ; i <= m ; i++)
dist[i] = INF;
for(ll i = 1 ; i <= m ; i++)
{
if(a[i].L == 1)
{
dist[i] = 0;
pq.push({0, i});
}
}
while(!pq.empty())
{
pll qq = pq.top();
pq.pop();
for(auto &i : vec[qq.se])
{
if(dist[i.fi] > dist[qq.se] + i.se)
{
dist[i.fi] = dist[qq.se] + i.se;
pq.push({-dist[i.fi], i.fi});
}
}
}
ans = INF;
for(ll i = 1 ; i <= m ; i++)
{
if(a[i].R == n)
ans = min(ans, dist[i] + a[i].C);
}
if(ans == INF)
cout << -1;
else
cout << ans;
}
int main(void)
{
fastio
cin >> n >> m;
for(ll i = 1 ; i <= m ; i++)
cin >> a[i].T >> a[i].L >> a[i].R >> a[i].C;
for(ll i = 1 ; i <= m ; i++)
{
for(ll j = 1 ; j <= m ; j++)
{
if(i == j)
continue;
if(a[i].R + a[i].T + 1 >= a[j].L + a[j].T && a[i].R - a[i].T + 1 >= a[j].L - a[j].T)
vec[i].push_back({j, a[i].C});
}
}
dijkstra();
return 0;
}
