N,M,X = map(int, input().split())
edge = [[] for i in range(N)]

for i in range(M):
    u,v,c,t = map(int, input().split())
    u-=1;v-=1
    edge[u].append((v,t+c/X))
    edge[v].append((u,t+c/X))

from heapq import *