from collections import deque,defaultdict
import heapq
N,M,X=map(int,input().split())
G=[[] for _ in range(N)]
C=defaultdict(int)
T=defaultdict(int)
for _ in range(M):
    u,v,c,t=map(int,input().split())
    u-=1;v-=1
    G[u].append(v)
    G[v].append(u)
    C[(u,v)]=c
    C[(v,u)]=c
    T[(u,v)]=t
    T[(v,u)]=t
vis=[(1<<60,1<<60,1<<60) for _ in range(N)] # t,c,m
attr=defaultdict(tuple)
hq=[]
heapq.heapify(hq)
hq.append((0,0,0,0)) # t,c,m,nxt
while hq:
    t,c,m,now=heapq.heappop(hq)
    vis[now]=(t,c,m)
    if now==N-1:break
    for nxt in G[now]:
        work=0
        if c+C[(now,nxt)]>m:
            work=(m-c+C[(now,nxt)]+X-1)//X
        if t+T[(now,nxt)]+work<vis[nxt][0] or \
            t+T[(now,nxt)]+work==vis[nxt][0] and c+C[(now,nxt)]<vis[nxt][1]:
            heapq.heappush(hq,((t+T[(now,nxt)]+work,c+C[(now,nxt)],m+X*work,nxt)))
if vis[N-1][0]==1<<60:print(-1)
else:print(vis[N-1][0])