N, M, X = map(int, input().split())
to = [[] for i in range(N)]
for i in range(M):
    u, v, a, b = map(int, input().split())
    to[u-1].append((v-1, a, b))
    to[v-1].append((u-1, a, b))

import heapq
ans = -1
v = [-1] * N

q = [(-(10**9), 0, 0)]
heapq.heapify(q)

while q:
    s, x, t = heapq.heappop(q)
    if v[x] > -s:
        continue

    for y, a, b in to[x]:
        if t + a > X:
            continue
        if v[y] > min(b, -s):
            continue
        heapq.heappush(q, (-min(b, -s), y, t+a))
        v[y] = min(b, -s)

print(min(v))