Algorithmics and C programming Language - Nicolas Gaud

Algorithmics and C programming Language - Nicolas Gaud

Algorithmics and C programming Language
LO27 –Fall 2015
https://moodle.utbm.fr
http://nico.gaud.free.fr
Nicolas Gaud
Université de Technologie de Belfort-Montbéliard
F-90 000 Belfort, France – [email protected]
N. Gaud
LO27 – F2015 – UTBM
Pointers on function
Université de Technologie de Belfort-Montbéliard
F-90 000 Belfort, France – [email protected]
Pointers on Function
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Pointers on Function
The function name is a symbolic constant (a pointer) referencing
the first executable instruction of this function in the CS.
For declaring a function’s pointer:
<returnedType> (*functionName)(<parameters>);
Example
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i n t swap ( i n t a , i n t b ) { . . . }
i n t (∗ p t r F c t ) ( i n t a , i n t b ) ;
p t r F c t = swap ;
swap ( 1 2 , 2 3 ) ; p t r F c t ( 1 2 , 2 3 ) ;
N. Gaud
LO27 – F2015 – UTBM
Pointers on Function: A concrete example
Pointers on Function: A concrete example
A function sorting an array of integer but externalizing the
comparison problem in a dedicated function.
N. Gaud
LO27 – F2015 – UTBM
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Pointers on Function: A concrete example
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t y p e d e f enum { FALSE , TRUE } b o o l ;
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void s o r t A r r a y ( i n t ∗ array , unsigned short size ,
bool (∗ comparator ) ( i n t a , i n t b ) ) {
unsigned short i , j ;
f o r ( i =0; i <s i z e −1; i ++) {
f o r ( j=i +1; j <s i z e ; j ++) {
i f ( ! comparator ( a r r a y [ i ] , a r r a y [ j ] ) )
swap ( a r r a y+i , a r r a y+j ) ;
}
}
}
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bool comparatorAscOrder ( i n t a , i n t b) {
r e t u r n ( a<=b ) ;
}
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v o i d main ( ) {
i n t t [ ] = {23 ,34 ,1 ,456 ,3 ,234455 ,3 , −134};
s o r t A r r a y ( t , 8 , comparatorAscOrder ) ;
}
N. Gaud
LO27 – F2015 – UTBM
Thank you for your attention. . .
Université de Technologie de Belfort-Montbéliard
F-90 000 Belfort, France – [email protected]
Appendix
Université de Technologie de Belfort-Montbéliard
F-90 000 Belfort, France – [email protected]
Author: Dr. Nicolas GAUD
Associate Professor
Laboratoire Systèmes and Transport (IRTES-SET)
Institut de Recherche sur les Transports, l’Énergie et la Société
Université de Technologie de Belfort-Montbéliard, France
Topics: Multiagent systems,
Multiagent-based simulation, Agent-Oriented
Software Engineering.
Web page:
Email:
http://multiagent.fr/People:Gaud_nicolas
[email protected]
See also his open-source contributions:
http://www.sarl.io
http://www.aspecs.org
http://www.janus-project.org
http://www.arakhne.org
N. Gaud
LO27 – F2015 – UTBM
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