# https://note.nkmk.me/python-union-find/
from collections import defaultdict


class UnionFind():
    def __init__(self, n):
        self.n = n
        self.parents = [-1] * n

    def find(self, x):
        if self.parents[x] < 0:
            return x
        else:
            self.parents[x] = self.find(self.parents[x])
            return self.parents[x]

    def union(self, x, y):
        x = self.find(x)
        y = self.find(y)

        if x == y:
            return

        if self.parents[x] > self.parents[y]:
            x, y = y, x

        self.parents[x] += self.parents[y]
        self.parents[y] = x

    def size(self, x):
        return -self.parents[self.find(x)]

    def same(self, x, y):
        return self.find(x) == self.find(y)

    def members(self, x):
        root = self.find(x)
        return [i for i in range(self.n) if self.find(i) == root]

    def roots(self):
        return [i for i, x in enumerate(self.parents) if x < 0]

    def group_count(self):
        return len(self.roots())

    def all_group_members(self):
        group_members = defaultdict(list)
        for member in range(self.n):
            group_members[self.find(member)].append(member)
        return group_members

    def __str__(self):
        return '\n'.join(f'{r}: {m}' for r, m in self.all_group_members().items())

N, M, X=map(int, input().split())
INPUT=tuple(tuple(map(int, input().split())) for i in range(M))
uf=UnionFind(N)
for elm in INPUT:
  u, v, _, __=elm
  u-=1; v-=1
  uf.union(u, v)
if uf.same(0, N-1)==False: print(-1); exit()
del uf

edge=[[] for i in range(N)]
for elm in INPUT:
  u, v, C, T=elm
  u-=1; v-=1
  edge[u].append((v, C, T))
  edge[v].append((u, C, T))

# 連結 ⇒ 移動可能

import heapq

d=[]

timeMIN=[None for i in range(N)]
heapq.heapify(d)

# 各タプルは (時間, - 残りのお金, 頂点) で入れる
heapq.heappush(d, (0, 0, 0))

while len(d)>0:
  t, mon, v=heapq.heappop(d)
  mon*=(-1)
  if timeMIN[v]==None: timeMIN[v]=t
  else: continue
  for nv, C, T in edge[v]:
    if timeMIN[nv]!=None: continue
    nt=t+T
    nmon=mon-C
    if nmon<0:
      nt+=(abs(nmon)+X-1)//X
      nmon%=X
    heapq.heappush(d, (nt, -nmon, nv))

print(timeMIN[N-1])