output_description: If the graph contains a negative cycle (a cycle whose sum of edge costs is a
  negative value) which is reachable from the source r, print
  
      
      
      NEGATIVE CYCLE
      
  
  in a line.
  
  Otherwise, print
  
      
      
      c0
      c1
      :
      c|V|-1
      
  
  The output consists of |V| lines. Print the cost of the shortest path from the
  source r to each vertex 0, 1, ... |V|-1 in order. If there is no path from the
  source to a vertex, print "INF".
input_description: An edge-weighted graph G (V, E) and the source r.
  
      
      
      |V| |E| r
      s0 t0 d0
      s1 t1 d1
      :
      s|E|-1 t|E|-1 d|E|-1
      
  
  |V| is the number of vertices and |E| is the number of edges in G. The graph
  vertices are named with the numbers 0, 1,..., |V|-1 respectively. r is the
  source of the graph.
  
  si and ti represent source and target vertices of i-th edge (directed) and di
  represents the cost of the i-th edge.
attempt: #!/usr/bin/python3
  
  import os
  import sys
  
  
  def main():
      V, E, R = read_ints()
      D = [tuple(read_ints()) for _ in range(E)]
      print(*solve(V, E, R, D), sep="\n")
  
  
  def solve(V, E, R, D):
      INF = 10001 * 1000
      dists = [INF] * V
      dists[R] = 0
      for _ in range(V - 1):
          for s, t, d in D:
              if dists[s] != INF and dists[t] > dists[s] + d:
                  dists[t] = dists[s] + d
  
      for s, t, d in D:
          if dists[s] != INF and dists[s] + d < dists[t]:
              return ["NEGATIVE CYCLE"]
  
      return ["INF" if d == INF else d for d in dists]
  
  
  ###############################################################################
  # AUXILIARY FUNCTIONS
  
  DEBUG = "DEBUG" in os.environ
  
  
  def inp():
      return sys.stdin.readline().rstrip()
  
  
  def read_int():
      return int(inp())
  
  
  def read_ints():
      return [int(e) for e in inp().split()]
  
  
  def dprint(*value, sep=" ", end="\n"):
      if DEBUG:
          print(*value, sep=sep, end=end)
  
  
  if __name__ == "__main__":
      main()
  
problem_description: Single Source Shortest Path (Negative Edges)
samples: [{"input": "4 5 0\n    0 1 2\n    0 2 3\n    1 2 -5\n    1 3 1\n    2 3 2", "output": "0\n    2\n    -3\n    -1"}, {"input": "4 6 0\n    0 1 2\n    0 2 3\n    1 2 -5\n    1 3 1\n    2 3 2\n    3 1 0", "output": "NEGATIVE CYCLE"}, {"input": "4 5 1\n    0 1 2\n    0 2 3\n    1 2 -5\n    1 3 1\n    2 3 2", "output": "INF\n    0\n    -5\n    -3"}]