Function & Recursion docx


Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
Data Structures
&
Algorithms

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:


Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
1. Function
2. The Concept Of Stack
3. The Sequence Of Execution During A Function Call
4. Parameter Passing & Call By Reference
5. Resolving Variable References
6. Recursion
7. Stack Overheads In Recursion
8. Writing A Recursive Function
9. Types Of Recursion

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:

–
 !"#$##%&'"
–
 (!)#"*# "!!""+",!#"*
–
-(!".'*

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
#  "$/#012#3

4
# 567
./#56787993
4
 5 9017
:
# 7
:

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
;-<
–
-stack  $'%%"!"#"#=!"#
>##= ",$+(""!!push"pop

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
?@AB--CC
–
When the funcon is called, the current execuon is temporarily stopped and the
control goes to the called funcon. Aer the call, the execuon resumes from the
point at which the execuon is stopped.
–
To get the exact point at which execuon is resumed, the address of #% )#
###%#"*. When the funcon call completes, the address
at the top of the stack is taken.

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
?@AB--CC
–
Funcons or sub-programs are implemented using a stack.

–
When a funcon is called, the address of the next instrucon is pushed
into the stack.
–
When the funcon is !nished, the address for execuon is taken by using
the pop operaon.

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
D--E-B
–
passing by value
•
#%"!,.""&#%"!! "#%" 
–
passing by reference
•
changed value aer the funcon completes

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
N=8
(Method)
N=8
(Method)
5F
5F
5F
5F
N=8

(Method)
N=8
(Method)
5F
5F
5G
5G
"+,$"!
"+,$.

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
./#3
4
5967
:
.;/#E3
4
E5E967
:
.?/#3
4
5967
:
By Value ???
By Reference???

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
FCB--HC
IJ%""",!",!,$+ !(!.2#%!"!
>+ (.


Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
K
- A method of programming whereby
a funcon directly or indirectly calls
itself
- Problems: stop recursion?

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
K

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
K

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
K
"#'
"#'

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
K

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
K

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
L-<-
–
' (#"#!#M#%(#%."#%#"*
%"


Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
GJB-
–
",!#'#"(+" ""#"!'"$%(
."(+" !',".#"*%"
–
"(+" $%"#(.$2
# "+2")(

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
N
–
C-/#$OP%3
–
-C/QR3
–
H-/%S(%T3
–
A-C/Q"#$O3
–
/!U+3
–
-C/#VW+%X3

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
N
–
C-
•

!$ "*"+!"!!##!."% #%.

Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
N
-
-C
"!". .!"
#"!2#%"!!#%!"##%+#%.&2
#%"!.#%"!!#
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Author: Trần Duy Thanh – Phone : 0987773061- Email: – Blog:
N
IA-C
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