This commit is contained in:
2026-07-04 12:48:16 +07:00
parent 6a18591a0b
commit 47d7e9f303
2 changed files with 48 additions and 22 deletions
+26 -14
View File
@@ -74,7 +74,7 @@ function runMCTS(
multithread=false,
)::NamedTuple{(:root, :bestNextState, :bestTerminalState, :highValueStateList),
Tuple{MCTSNode,T,T,Vector{Dict{String,Any}}}} where {T<:Any}
println("--> LLMMCTS runMCTS 1")
# Initialize the MCTS tree with a root node representing the initial state
# root.visits=0: no visits yet
# root.statevalue=0: no simulation results yet
@@ -91,33 +91,38 @@ function runMCTS(
# Start from root and traverse down using UCT selection
node = root
node.visits += 1 # Count this iteration's visit to root
println("--> LLMMCTS runMCTS 2")
# Phase 1: SELECTION - Traverse tree using UCT until reaching a leaf node
# UCT balances exploration (new branches) vs exploitation (promising branches)
while !isleaf(node)
println("--> LLMMCTS runMCTS 3")
node = UCTselect(node, explorationweight)
end
println("--> LLMMCTS runMCTS 4")
# Phase 2: TERMINAL CHECK - If leaf is terminal, just backpropagate
if node.isterminal
println("--> LLMMCTS runMCTS 5")
# If this terminal state has high reward (>= 8), store it for later
if node.state[:reward] >= 8
println("--> LLMMCTS runMCTS 6")
put!(highValueState, deepcopy(node.state))
end
println("--> LLMMCTS runMCTS 7")
# Backpropagate the terminal node's own reward up to root
# This updates all ancestors with this path's outcome
backpropagate(node, node.reward)
else
println("--> LLMMCTS runMCTS 8")
# Phase 3: EXPANSION - Generate children for this non-terminal leaf
# Horizontal sampling: create multiple child nodes via LLM transition
_ = expand(node, transition, transitionargs;
horizontalSample=horizontalSampleExpansionPhase,
multithread=multithread)
println("--> LLMMCTS runMCTS 9")
# Phase 4: SIMULATION + BACKPROPAGATION
# For each newly expanded child, run simulation and update statistics
if multithread
println("--> LLMMCTS runMCTS 10")
# Parallel simulation: spawn threads for each child node
@sync for (leafNodeKey, leafNode) in node.children
@spawn simulateThenBackpropagate(leafNode, transition, transitionargs;
@@ -129,8 +134,10 @@ function runMCTS(
)
end
else
println("--> LLMMCTS runMCTS 11")
# Sequential simulation: process each child one at a time
for (leafNodeKey, leafNode) in node.children
println("--> LLMMCTS runMCTS 11-1")
simulateThenBackpropagate(leafNode, transition, transitionargs;
maxSimulationDepth=maxSimulationDepth,
horizontalSampleSimulationPhase=horizontalSampleSimulationPhase,
@@ -140,27 +147,29 @@ function runMCTS(
end
end
end
println("--> LLMMCTS runMCTS 12")
# Phase 5: EARLY STOP CHECK
# Optional: stop search early if a condition is met
if typeof(earlystop) <: Function && earlystop(node.state)
println("--> LLMMCTS runMCTS 13")
break
end
end
println("--> LLMMCTS runMCTS 14")
# After all iterations, extract results from the search tree
# Select best immediate next state (best child of root)
bestNextState = selectBestNextNode(root)
println("--> LLMMCTS runMCTS 15")
# Select best terminal state along the optimal trajectory
bestTerminalState = selectBestTrajectoryNode(root)
# Collect all high-value states from the channel into a list
highValueStateList = Vector{Dict{String, Any}}()
while !isempty(highValueState)
println("--> LLMMCTS runMCTS 16")
push!(highValueStateList, take!(highValueState))
end
println("--> LLMMCTS runMCTS 17")
# Return complete search results
result = (
root=root,
@@ -209,6 +218,7 @@ function simulateThenBackpropagate(node::MCTSNode, transition::Function, transit
saveSimulatedNode::Bool=false,
multithread=false,
highValueState=Union{Nothing,Any}=nothing)
println("--> LLMMCTS simulateThenBackpropagate 1")
# Phase 1: RUN SIMULATION (rollout)
# Perform a rollout from this node, accumulating rewards along the way
simTrajectoryReward, terminalstate =
@@ -216,28 +226,30 @@ function simulateThenBackpropagate(node::MCTSNode, transition::Function, transit
maxSimulationDepth=maxSimulationDepth,
horizontalSample=horizontalSampleSimulationPhase,
multithread=multithread)
println("--> LLMMCTS simulateThenBackpropagate 2")
# Phase 2: HIGH-VALUE STATE TRACKING
# If we reached a terminal state with high reward (>= 8), store it
# This allows users to access multiple good solutions, not just the best one
if highValueState !== nothing &&
terminalstate !== nothing &&
terminalstate[:reward] >= 8
terminalstate["reward"] >= 8
println("--> LLMMCTS simulateThenBackpropagate 3")
put!(highValueState, deepcopy(terminalstate))
end
println("--> LLMMCTS simulateThenBackpropagate 4")
# Phase 3: BACKPROPAGATE
# Update statistics (visits, statevalue) for all ancestors up to root
# The simulation result is now incorporated into the tree
backpropagate(node, simTrajectoryReward)
println("--> LLMMCTS simulateThenBackpropagate 5")
# Phase 4: MEMORY MANAGEMENT
# Clear children unless user wants to keep them for analysis
# This frees memory for the next iteration while preserving tree structure
if saveSimulatedNode == false
println("--> LLMMCTS simulateThenBackpropagate 6")
node.children = Dict{String, MCTSNode}()
end
println("--> LLMMCTS simulateThenBackpropagate 7")
end