#include <bits/stdc++.h>
#define maxn 100005
#define INF 9223372036854775807LL
using namespace std;
using Road = tuple<int, int, int>;
using LL = long long;
using pli = pair<LL, int>;
vector<Road> G[maxn];
LL dist[maxn];
int main()
{
	int n, m;
	scanf("%d%d", &n, &m);
	while(m--)
	{
		int a, b, c, d;
		scanf("%d%d%d%d", &a, &b, &c, &d);
		if(--a == --b) continue;
		G[a].emplace_back(b, c, d);
		G[b].emplace_back(a, c, d);
	}
	dist[0] = 0LL;
	for(int i=1; i<n; i++) dist[i] = INF;
	priority_queue<pli, vector<pli>, greater<pli>> q;
	q.emplace(0LL, 0);
	while(!q.empty())
	{
		auto [t, u] = q.top(); q.pop();
		if(dist[u] != t) continue;
		for(auto [v, c, d]: G[u])
		{
			LL t2 = sqrt((long double) d) - 0.5;
			if(t2 < t) t2 = t;
			t2 += LL(c) + LL(d) / (t2 + 1LL);
			if(t2 < dist[v])
				q.emplace(dist[v] = t2, v);
		}
	}
	if(dist[n - 1] == INF) puts("-1");
	else printf("%lld\n", dist[n - 1]);
	return 0;
}
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
 
#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
 
typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
 
typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
 
#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)
#define trav(a,x) for (auto& a : x)
#define uid(a, b) uniform_int_distribution<int>(a, b)(rng)
 
#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
#define ins insert

template<class T> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
 
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
 
const int MOD = 1000000007;
const char nl = '\n';
const int MX = 100001; //check the limits, dummy

void solve() {

    int N, S, D; cin >> N >> S >> D;
    F0R(i, N) {
        int X, Y; cin >> X >> Y;
        if (X < S && Y > D) {
            cout << "Yes" << nl; return;
        }
    }
    cout << "No" << nl;

}
 
int main() {
	ios_base::sync_with_stdio(0); cin.tie(0);    

    int T = 1;
//    cin >> T;
    while(T--) {
        solve();
    }

	return 0;
}
 
// read the question correctly (ll vs int)
// template by bqi343

