update

src/interface.jl

@@ -52,7 +52,8 @@ function runMCTS(
   earlystop::Union{Function,Nothing}=nothing
 )::NamedTuple{(:bestNextState, :bestFinalState),Tuple{T,T}} where {T<:Any}
 
-  root = MCTSNode("root", initialstate, 0, 0, 0, 0, false, nothing, Dict{String,MCTSNode}())
+  root = MCTSNode("root", initialstate, 0, 0, 0, 0, false, nothing, Dict{String,MCTSNode}(),
+                  Dict{Symbol,Any}())
 
   for nth in 1:maxiterations
     node = root
@@ -67,7 +68,7 @@ function runMCTS(
       # do nothing then go directly to backpropagation. It means the end of this iteration
       backpropagate(node, node.reward)
     else
-      expand(node, transition, transitionargs;
+      _ = expand(node, transition, transitionargs;
         totalsample=totalsample)
       leafNode = selectChildNode(node)
       simTrajectoryReward, terminalstate = simulate(leafNode, transition, transitionargs;
@@ -82,6 +83,9 @@ function runMCTS(
       # end
 
       backpropagate(leafNode, simTrajectoryReward)
+
+      # delete all child node, no need for child node that was created during simulation
+      leafNode.children = Dict{String,MCTSNode}() 
     end
 
     # stop if the early stop condition is met