John Hopcroft

Cornell University

John Edward Hopcroft is an American theoretical computer scientist at Cornell University who, together with Robert Tarjan, received the 1986 ACM Turing Award for fundamental achievements in the design and analysis of algorithms and data structures. Hopcroft and Tarjan are credited with numerous algorithms and data structures that form the core of computer science education and practice: the Hopcroft-Karp algorithm for maximum bipartite matching, Hopcroft's algorithm for DFA minimization, and foundational work on planarity testing, biconnected components, and depth-first search. Hopcroft and Jeffrey Ullman co-authored the textbook Introduction to Automata Theory, Languages, and Computation, which became the definitive text on formal language theory and computability. He has also contributed to the formal analysis of programs, program verification, and the theory of computational complexity. More recently, Hopcroft has been active in computing education and advocating for new approaches to teaching computer science globally, with emphasis on China and India.