import sys

# sys.setrecursionlimit(200005)
# sys.set_int_max_str_digits(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()

dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
# inf = -1-(-1 << 31)
inf = -1-(-1 << 62)

# md = 10**9+7
md = 998244353

from heapq import *

def dijkstra(to, root=0):
    n = len(to)
    dist = [(inf, inf)]*n
    dist[root] = (0, 0)
    hp = [(0, 0, root)]
    while hp:
        d, m, u = heappop(hp)
        if (d, m) > dist[u]: continue
        for v, c, t in to[u]:
            nd = d+t+(m+c)//x
            nm = (m+c)%x
            if dist[v] <= (nd, nm): continue
            dist[v] = (nd, nm)
            heappush(hp, (nd, nm, v))

    return dist

n, m, x = LI()
to = [[] for _ in range(n)]
for _ in range(m):
    u, v, c, t = LI()
    u, v = u-1, v-1
    to[u].append((v, c, t))
    to[v].append((u, c, t))

dist=dijkstra(to)
ans=dist[-1][0]
if ans==inf:
    print(-1)
else:
    if dist[-1][1]:ans+=1
    print(ans)