CHOICE OF A PROGRAMMING LANGUAGE FOR PROGRAMMING OF OPTIMIZATION METHODS

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1 Journal of Information, Control and Management Systems, Vol. 4, (2006), No CHOICE OF A PROGRAMMING LANGUAGE FOR PROGRAMMING OF OPTIMIZATION METHODS Michal HRČKA University of Žilina, Faculty of Management Science and Informatics, Slovak Republic Michal.Hrcka@fria.fri.utc.sk Abstract The essential part of testing and applying optimization techniques is creation of optimization programs. Programming languages commonly used for creation stand alone applications in this field of research are C, C++ and Pascal. C language can be classified as a highest low level programming language. Object oriented language derived from C, called C++ merges advantages of object oriented and structured programming. Pascal is today also an object oriented programming language, as C++, and it also offers objects and structured programming. The question is: which one of these three languages is the fastest for processing optimization tasks. Keywords: optimization, minimum spanning tree, programming language, C, C++, Pascal 1 C LANGUAGE Is universal, procedural, low level programming language. C has very compact grammar. This language has no specialization for special scope of applications. At the beginning it was designed and implemented under UNIX, almost all UNIX is written in C, but it is not platform or operating system dependent. Low level language means, that C works directly with standard data types such as characters, integers, real numbers etc. Doesn t allow direct work with strings, arrays, and doesn t contain tools for input and output. These functions are necessary to execute with use of library functions. This feature has some advantages: simple language simple compiler high code efficiency (similar to the assembly language)

2 86 Choice of Programming Language for Programming Optimization Methods Brian W. Kernighan and Denis developed first language standard M. Richie, described in the book The C Programming Language. This book issued in 1978, describing language standards is called as K&R standard. Today official standard is ANSI C from 1990, which was built on K&R standard. This standard includes exact description of the function set and header (.h) file set that has to be contained in every implementation of ANSI C compiler. The way of processing source code in C language is shown on figure 1. Figure 1 Building program from C source code 2 C++ LANGUAGE C also has had a great influence on many other popular languages, especially C++ which was originally designed as an enhancement to C. Together with raising requirements on developers there comes the need to create more systematic (reusable) source code. As the developers skip from assembly programming into C programming, there was also a need to simplify the usage of this language. Popular language C gets an object-oriented successor developed from its own syntax, the C++ language. C++ as the C allows creating own structures and in addition it allows to add object oriented programming (OOP) techniques, such as: inheritance polymorphism access privileges In C++ techniques not related with OOP are also implemented. This increases flexibility by using existing source code multiple times. The mentioned techniques are: method overloading operator functions operator overloading template programming As a successor of C language, they have many similarities. Compilation of a source code in C++ is shown on figure 2.

3 Journal of Information, Control and Management Systems, Vol. 4, (2006), No Figure 2 Building program from C++ source code Source files containing code in C++ (.cpp,.hpp,.h) are translated into assembly language, which is compiled separately [4]. Older compilers compile the source C++ at first into C and then into assembly language [3]. From the reader s point of view the code written in C++ is more understandable in comparison with the source code written in C. 3 PASCAL LANGUAGE The history of Pascal programming language started in In this year developed Niklaus Wirth the first version. In 1970 it was implemented on DCD 6000 computers. With continuous development the language was enhanced and from 1983 the Pascal came to the ISO standard. In November 1983 was developed first version of Turbo Pascal, until 1987 other 4 enhancements had been developed. In 1995 the new tool for windows programming called Delphi was introduced. The Delphi was developed as RAD (Rapid Application Development) tool. The way of processing Pascal source code into executable program is shown on figure 3. Figure 3 Building program from Pascal source code The advantage of Pascal (used in Delphi) is its readability. You can read Pascal source code without deep knowledge of Pascal, in C language it isn t possible. On the other side is this readability balanced with lower speed of the executable program generated by Delphi compiler.

4 88 Choice of Programming Language for Programming Optimization Methods 4 TESTING For the purpose of testing I used Kruskal algorithm. Kruskal algorithm is used to find minimum spanning tree [1]. For sorting in the first step of finding minimum spanning tree I used quick sort algorithm. In all three cases (C, C++, Pascal) there is method qsort already implemented. For processing C source code I used gcc compiler accessible under GNU-GPL license issued by Free Software Foundation. Code was optimized for speed (-O2 optimization). For processing C++ code I used the same compiler, with the same optimization O2. Pascal compiler was Delphi version 7.0. There was turned on optimization and turned off generating of the debug information (figure 4). Compiling and testing was done on computer with Windows XP Professional operating system, service pack 2. RAM memory size was 512MB, with CPU AMD Athlon 2.5 GHz. Figure 4 Delphi compiler settings 5 CONCLUSIONS The reached times for calculation of minimum spanning tree together with graphs sizes (vertices count and edges count) are shown in Table 1. These results are also shown in Graph 1. The performance difference is noticeable. The program in C runs on average 6.36 times faster than program made in Delphi. When comparing C and C++, the C program runs 3.86 times faster on average.

5 Journal of Information, Control and Management Systems, Vol. 4, (2006), No Table 1 Results reached with C, C++ and Pascal program graph name V E time [ms] C C++ Delphi C++/C Delphi/C alue alue alue alue alue alue alue alue alue alue alue alue alue alue alue alut alut alut Graf 1 Speed of the programs written in C/C++/Delphi ti m e [m C C++ Delphi alue2087 alue2105 alue3146 alue5067 alue5345 alue5623 alue5901 alue6179 alue6457 alue6735 alue6951 alue7065 alue7066 alue7080 alue7229 alut0787 alut0805 alut1181

6 90 Choice of Programming Language for Programming Optimization Methods REFERENCES [1] PLESNÍK J.: Grafové Algoritmy. VEDA. Bratislava [2] TEIXEIRA STEVE, XAVIER PACHECO: Borland Delphi 6 Developer s Guide. Sams Publishing. Indianapolis [3] FRANK B. BROKKEN: C++ Annotations Version 4.4.0c. University of Groningen [4] R. Alexander, G. Bensley: C++ Footprint and Performance Optimization. Sams Publishing. Indianapolis. 2000

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