nc = 0
for nnma, node in pairs(self.node) do
for _, nnmb in pairs(node.succ) do
nc = 0
for nnma, node in pairs(self.node) do
for _, nnmb in pairs(node.succ) do
table.insert(self.node[pred[1]].gradInputSucc, nnm.gradInput)
elseif #pred > 1 then
assert(torch.type(nnm.gradInput) == 'table',
table.insert(self.node[pred[1]].gradInputSucc, nnm.gradInput)
elseif #pred > 1 then
assert(torch.type(nnm.gradInput) == 'table',