# D. Scott
# CCI - Problem 4.1
# Determine whether two nodes (S and E) in a directed graph are connected

import sys

nodes = ['A','L','K','S','P','E','V','F','R']
adj = {'A':('S'),'L':('A'),'K':('L'),'S':(),'V':('F','R'),'F':('P'),'P':('K'),
       'R':(),'E':('V','F')}
seen = []
path = []

curr = 'E'
target = 'S'
found = False

def searchGraph(n):
  if (n not in seen):
    path.append(n)
    print("Checking ",n,"...")
    if(n == target):
      print("\nThere is a path from ",curr," to ",target)
      print(path)
      raise SystemExit
    seen.append(n)
    for x in adj:
      if (x == n):
        print("Checking adjacent list of ",x,"...")
        for y in adj[x]:
          searchGraph(y)

searchGraph(curr)
if (found == False):
  print("\nThere is no path from ",curr," to ",target)