Title	Code	Difficulty	Recommend	Prerequisites
Learning Combinatorial Optimization Algorithms over Graphs (2017)	official	★☆	★★☆	S2V, Q-learning
Learning Heuristics for the TSP by Policy Gradient (2018)	none	★☆	★★★	Transformers, PG
Attention, Learn to Solve Routing Problems! (2018)	official	★★★	★★☆	Transformers, Self-critical Training
POMO: Policy Optimization with Multiple Optima for Reinforcement Learning (2020)	official	★★	★★★	Greedy-rollout
Generalize a Small Pre-trained Model to Arbitrarily Large TSP Instances (2020)	official	★★☆	★★★★	MCTS, Att-GCRN
Learning Heuristics for the TSP by Policy Gradient (2021)	none	★★	★★★	2-opt, LS, AC
The Transformer Network for the Traveling Salesman Problem (2021)	none	★	★	Transformers, TD
Reinforcement Learning for Route Optimization with Robustness Guarantees (2021)	none	★★	★★	DNQ
Combining Reinforcement Learning with SOTA algorithm called Lin-Kernighan-Helsgaun Algorithm for the Traveling Salesman Problem (2021)	official	★★	★★☆	LKH, TD
Graph Neural Network Guided Local Search for the Traveling Salesperson Problem (2022)	official	★★	★★★☆	GLS, regret algorithm
DIMES: A Differentiable Meta Solver for Combinatorial Optimization Problems (2022)	official	★★	★★★	DL Basic
Simulation-guided Beam Search for Neural Combinatorial Optimization (2022)	official	★☆	★★★	Active Search, MCBS
Sym-NCO: Leveraging Symmetricity for Neural Combinatorial Optimization (2022)	official	★	★★	POMO