import heapq
N,M,X = map(int,input().split())
G = {i:[] for i in range(1,N+1)}
for _ in range(M):
    u,v,c,t = map(int,input().split())
    G[u].append((v,c,t))
    G[v].append((u,c,t))
INFTY = 10**12
ans = INFTY
high = INFTY
low = 0
while high-low>1:
    mid = (high+low)//2
    dist = [INFTY]*(N+1)
    visit = [0]*(N+1)
    k = (mid+X-1)//X
    que = [(k,1,k*X)]
    dist[1] = k
    while que:
        t,v,c = heapq.heappop(que)
        if t>dist[v]:continue
        visit[v] = 1
        for u,dc,dt in G[v]:
            if visit[u]==1:continue
            if c>=dc:
                nc = c-dc
                nt = t+dt
                if nt<dist[u]:
                    dist[u] = nt
                    heapq.heappush(que,(nt,u,nc))
    if dist[N]<INFTY:
        high = mid
        ans = min(ans,dist[N])
    else:
        low = mid
if ans==INFTY:
    print(-1)
else:
    print(ans)