Two Languages for Estimating Program Efficiency Two languages enabling their users to estimate the efficiency of computer programs are presented. The program whose efficiency one wishes to estimate is written in the first language, a go-to-less programming language which includes most of the features of Algol 60. The second language consists of interactive commands enabling its users to provide additional information about the program written in the first language and to output results estimating its efficiency. Processors for the two languages are also described. The first processor is a syntax-directed translator which compiles a program into a symbolic formula representing the execution time for that program. The sound processor is a set of procedures for that program. The second processor is a set of procedures for algebraic manipulation which can be called by the user to operate on the formula produced by the first processor. Examples of the usage of the two languages are included. The limitations of the present system, its relation to Knuth's work on the analysis of algorithms, and some of the directions for further research are also discussed. CACM June, 1974 CCohen, J. Zuckerman, C. programming languages, syntax-directed translation, symbolic manipulation, program efficiency, analysis of algorithms 4.12 4.20 5.24 5.25 CA740601 JB January 17, 1978 3:48 PM 1086 4 2645 1132 4 2645 1234 4 2645 1263 4 2645 1265 4 2645 1270 4 2645 1323 4 2645 1358 4 2645 1379 4 2645 1380 4 2645 1453 4 2645 1464 4 2645 1484 4 2645 1491 4 2645 1498 4 2645 1613 4 2645 1614 4 2645 1781 4 2645 1825 4 2645 1860 4 2645 2083 4 2645 2178 4 2645 2179 4 2645 2252 4 2645 2325 4 2645 2341 4 2645 2546 4 2645 2645 4 2645 2652 4 2645 2684 4 2645 2842 4 2645 2929 4 2645 2934 4 2645 3069 4 2645 669 4 2645 679 4 2645 691 4 2645 761 4 2645 949 4 2645 989 4 2645 2645 5 2645 2645 5 2645 2645 5 2645 2719 5 2645 3094 5 2645 3184 5 2645 1265 6 2645 1626 6 2645 210 6 2645 2151 6 2645 2167 6 2645 2179 6 2645 2210 6 2645 2645 6 2645 2645 6 2645 2657 6 2645