This book constitutes the refereed proceedings of the 40th National Conference on Theoretical Computer Science, NCTCS 2022, held in Changchun, China, during July 29-31, 2022. The 13 full papers and 6 short papers included in this book were carefully reviewed and selected from 58 submissions. They were organized in topical sections as follows: computational theory and model; approximation algorithms; artificial intelligence; and system and resource scheduling.

This book constitutes the thoroughly refereed proceedings of the 39th National Conference of Theoretical Computer Science, NCTCS 2021, held in Yinchuan, China, in July 2021. The 67 full papers were carefully reviewed and selected from 145 submissions, and 14 of them were selected for the volume. The papers present recent research in the areas of information hiding, data detection and recognition, system scheduling, time series prediction, and formal analysis.

This book constitutes the thoroughly refereed proceedings of the 38th National Conference of Theoretical Computer Science, NCTCS 2020, held in Nanning, China, in November 2020. The 13 full papers presented were carefully reviewed and selected from 28 submissions. They present recent research in the areas of algorithms and complexity, matrix computation; deep learning; network communication and security.