An early mechanism for the distribution of useful implementations of algorithms was CALGO , the Collected Algorithms of the ACM. It first appeared in Communications of the ACM in 1960, covering such famous algorithms as Floyd's linear-time build heap algorithm. More recently, it has been the province of ACM Transactions on Mathematical Software. Each algorithm/implementation is described in a brief journal article, with the implementation validated and collected.

A total of 750 algorithms have appeared to date. Most of the codes are in Fortran, and of interest in numerical computing, although several interesting combinatorial algorithms have slithered into CALGO. Since the implementations have been refereed, presumably they are more reliable than most freely available software. All the implementations below are available by ftp or WWW from Netlib. Algorithms of combinatorial interest include:

• Bandwidth -- 508 509 529 582
• Convex Hull -- 523
• Cryptography -- 536
• Decision Trees -- 606
• Fourier Transforms -- 545
• Generating Partitions -- 403
• Generating Subsets -- 515
• Geometric Primitives -- 550
• Hamiltonian Cycle -- 595
• High Precision Arithmetic -- 693
• Knapsack -- 632
• Linear Programming -- 551 552 559
• Matching -- 548 575
• Matrix Inversion -- 645
• Minimum Cut (facility location) -- 558
• Minimum Spanning Trees -- 479 613
• Priority Queues -- 561
• Random Numbers -- 488 599 712
• Scheduling -- 520
• Shortest Path -- 562
• Solving Linear Equations -- 533 576 578
• Sorting -- 410 505
• Sparse Matrix -- 601
• Text Compression - 673
• Traveling Salesman Problem -- 608 750
• Triangulation -- 624
• Unconstrained Optimization -- 500 566 611 630 702 734 739 744