Value Error: Too many values to unpack
<p>When I execute it, it is giving me an eror i.e too many values to unpack?
How do i make it to work properly. </p>

<pre><code>  stack = util.Stack()
  closed = []
  child = []
  index = 0
  currNode = problem.getStartState()
  node = currNode
  stack.push(node)
  while not stack.isEmpty():
     node = stack.pop()
     if problem.isGoalState(node):
        print "true"
        closed.append(node)
     else:
         child = problem.getSuccessors(node)
         for nodes in child:
            stack.push(nodes)
         closed.append(node)
  return None      
</code></pre>

<p>Error is:</p>

<pre><code> File  line 90, in depthFirstSearch
    child = problem.getSuccessors(node)
  File  line 179, in getSuccessors
    x,y = state
**ValueError: too many values to unpack**
</code></pre>

<p>The code for the getsuccessor func is:</p>

<pre><code>def getSuccessors(self, state):
    """
    Returns successor states, the actions they require, and a cost of 1.

     """

    successors = []
    for action in [Directions.NORTH, Directions.SOUTH, Directions.EAST, Directions.WEST]:
      x,y = state
      dx, dy = Actions.directionToVector(action)
      nextx, nexty = int(x + dx), int(y + dy)
      if not self.walls[nextx][nexty]:
        nextState = (nextx, nexty)
        cost = self.costFn(nextState)
        successors.append( ( nextState, action, cost) )
</code></pre>

<p>The values returned for this function initially:</p>

<pre><code>problem.getStartState() - (5, 5)
problem.isGoalState(problem.getStartState())- False
 problem.getSuccessors(problem.getStartState()) - [((5, 4), 'South', 1), ((4, 5), 'West', 1)]
</code></pre>
