Board : CBSE Class : 12 Subject : Python Concept : Binary search using recursion in Python

1. GVK CHINMAYA VIDYALAYA
SENIOR SECONDARY SCHOOL
Kothuru, Indukurupet, SPS Nellore
Binary Search
Class: 12 Subject: Python Teacher: C Vijaya Kumar
B.Tech,MBA

2. 2 3 4 10 40
high>=low:
4>=0
TRUE
mid=2
LOW HIGHMID

3. 2 3 4 10 40
If arr[mid]==10:
arr[2]==10:
4 = 10
FALSE
LOW HIGHMID

4. 2 3 4 10 40
Elif arr[mid]>x:
arr[2]>10:
4>10:
FALSE
LOW HIGHMID

5. 2 3 4 10 40
binary(arr,3,4,10)
LOW HIGH

6. 2 3 4 10 40
binary(arr,3,4,10)
If high>=low:
4>=3:
TRUE
mid=3
LOW,MID HIGH

7. 2 3 4 10 40
arr[3]==10
TRUE
LOW and MID HIGH

8. 2 3 4 10 40
Mid value is
returned here
LOW and MID HIGH

9. 2 3 4 10 40
result=3
LOW and MID HIGH

10. 2 3 4 10 40
If 3 not equal to -1:
Item found
LOW and MID HIGH

11. Lets us see the flow of execution of item not found in the same binary search

12. 2 3 4 10 40
HIGHLOW
def binary(arr,0,4,41):

13. 2 3 4 10 40
HIGHLOW
If 4>=0:
TRUE
mid=2
MID

14. 2 3 4 10 40
HIGHLOW
If 4==41:
False
MID

15. 2 3 4 10 40
HIGHLOW
elif 4 > 41:
False
MID

16. 2 3 4 10 40
HIGHLOW
binary(arr,3,4,41):
MID

17. 2 3 4 10 40
HIGHLOW
binary(arr,3,4,41):

18. 2 3 4 10 40
HIGHLOW and MID
If 4 > 3:
TRUE
mid=3

19. 2 3 4 10 40
HIGHLOW and MID
elif 10 > 41:
FALSE

20. 2 3 4 10 40
HIGHLOW and MID
binary(arr,4,4,41)

21. 2 3 4 10 40
LOW and HIGH
binary(arr,4,4,41)

22. 2 3 4 10 40
MID,LOW and HIGH
If 4 >= 4:
TRUE
Mid = 4

23. 2 3 4 10 40
MID,LOW and HIGH
if 40 == 41:
FALSE

24. 2 3 4 10 40
MID,LOW and HIGH
elif 40 > 41:
FALSE

25. 2 3 4 10 40
MID,LOW and HIGH
binary (arr,5,4,41):

26. 2 3 4 10 40
HIGH
binary (arr,5,4,41):
Low = 5
High = 4
X = 41

27. 2 3 4 10 40
HIGH
If 4>=5:
FALSE

28. 2 3 4 10 40
HIGH
Return -1

29. 2 3 4 10 40
HIGH
Return -1 (Third Recursive Call)

30. 2 3 4 10 40
HIGH
Return -1 (Second recursive call)

31. 2 3 4 10 40
HIGH
Return -1 (First recursive call)

32. 2 3 4 10 40
HIGH
Result = -1

33. 2 3 4 10 40
HIGH
If False:
Else
print(“element not present in array”)