#include <bits/stdc++.h>
using namespace std;
using ll = long long;
struct Segment {
int t, l, r, w;
};
constexpr ll inf = 3e18;
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, m;
cin >> n >> m;
vector<Segment> s(m);
vector<int> tt;
for (auto &[t, l, r, w] : s) {
cin >> t >> l >> r >> w;
tt.push_back(t);
}
sort(tt.begin(), tt.end());
tt.resize(unique(tt.begin(), tt.end()) - tt.begin());
const int siz = tt.size();
vector<int> pnt1(siz + 1), pnt2(siz + 1), pos(m);
vector<vector<pair<ll, int>>> fn1(siz + 1), fn2(siz + 1);
vector<pair<ll, int>> val1(m), val2(m);
priority_queue<pair<ll, int>, vector<pair<ll, int>>, greater<>> pq;
vector<ll> dp(m, inf);
vector<bool> used(m);
for (int i = 0; i < m; ++i) {
pos[i] = lower_bound(tt.begin(), tt.end(), s[i].t) - tt.begin();
val1[i] = {-s[i].l + s[i].t + 1, i};
val2[i] = {-s[i].l - s[i].t + 1, i};
}
sort(val1.rbegin(), val1.rend());
sort(val2.rbegin(), val2.rend());
for (auto [v, i] : val1) {
for (int x = pos[i] + 1; x <= siz; x += x & -x) {
fn1[x].emplace_back(v, i);
}
}
for (auto [v, i] : val2) {
for (int x = pos[i] + 1; x > 0; x -= x & -x) {
fn2[x].emplace_back(v, i);
}
}
auto take = [&](int i, ll val) {
if (used[i]) {
return;
}
dp[i] = val + s[i].w;
pq.emplace(dp[i], i);
used[i] = true;
};
for (int i = 0; i < m; ++i) {
if (s[i].l == 1) {
take(i, 0);
}
}
while (!pq.empty()) {
auto [d, i] = pq.top();
pq.pop();
ll v1 = s[i].t - s[i].r, v2 = -s[i].r - s[i].t;
for (int x = pos[i] + 1; x > 0; x -= x & -x) {
while (pnt1[x] < size(fn1[x]) && fn1[x][pnt1[x]].first >= v1) {
take(fn1[x][pnt1[x]++].second, d);
}
}
for (int x = pos[i] + 1; x <= siz; x += x & -x) {
while (pnt2[x] < size(fn2[x]) && fn2[x][pnt2[x]].first >= v2) {
take(fn2[x][pnt2[x]++].second, d);
}
}
}
ll ans = inf;
for (int i = 0; i < m; ++i) {
if (s[i].r == n) {
ans = min(ans, dp[i]);
}
}
if (ans == inf) {
cout << "-1\n";
} else {
cout << ans << '\n';
}
return 0;
}
