WAP to print all primes using Sieve of Eratosthenes method

1. Team Emertxe
Basic Refresher

2. Assignment 12

3. Assignment 12

4. Assignment 12
WAP to print all prime numbers <= ‘num’ using Sieve of
Eratosthenes method.

5. Assignment 12
WAP to print all prime numbers <= ‘num’ using Sieve of
Eratosthenes method.
Input:

6. Assignment 12
WAP to print all prime numbers <= ‘num’ using Sieve of
Eratosthenes method.
Input: Read integer ‘num’

7. Assignment 12
WAP to print all prime numbers <= ‘num’ using Sieve of
Eratosthenes method.
Input: Read integer ‘num’
Output:

8. Assignment 12
WAP to print all prime numbers <= ‘num’ using Sieve of
Eratosthenes method.
Input: Read integer ‘num’
Output: Print the prime numbers less than or equal to ‘num’

9. Assignment 12
What is a Prime number?

10. Assignment 12
What is a Prime number?
 A number that is divisible only by itself and 1.

11. Assignment 12
What is a Prime number?
 A number that is divisible only by itself and 1.
 Examples: 2, 3, 5, 7, 11 etc.

12. Assignment 12
Sieve of Eratosthenes:-

13. Assignment 12
Sieve of Eratosthenes:-
⮚The sieve of Eratosthenes is one of the most efficient ways to
find all of the smaller primes.

14. Assignment 12
Sieve of Eratosthenes:-
⮚The sieve of Eratosthenes is one of the most efficient ways to
find all of the smaller primes.
⮚Generate a list of integers from 2 to 20

15. Assignment 12
Sieve of Eratosthenes:-
⮚The sieve of Eratosthenes is one of the most efficient ways to
find all of the smaller primes.
⮚Generate a list of integers from 2 to 20
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

16. Assignment 12
Sieve of Eratosthenes:-
⮚The sieve of Eratosthenes is one of the most efficient ways to
find all of the smaller primes.
⮚Generate a list of integers from 2 to 20
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

17. Assignment 12
Sieve of Eratosthenes:-
⮚The first number in the list is 2; cross out every multiples of
2.

18. Assignment 12
Sieve of Eratosthenes:-
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
X
i
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

19. Assignment 12
Sieve of Eratosthenes:-
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
X X
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
i

20. Assignment 12
Sieve of Eratosthenes:-
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
X X X
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
i

21. Assignment 12
Sieve of Eratosthenes:-
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
X X X
X X
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
i

22. Assignment 12
Sieve of Eratosthenes:-
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
X X X
X X X
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
i

23. Assignment 12
Sieve of Eratosthenes:-
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
X X X
X X X X
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
i

24. Assignment 12
Sieve of Eratosthenes:-
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
X X X
X X X X X
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
i

25. Assignment 12
Sieve of Eratosthenes:-
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
X X X
X X X X X X
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
i

26. Assignment 12
Sieve of Eratosthenes:-
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
X X X
X X X X X X X
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
i

27. Assignment 12
Sieve of Eratosthenes:-
⮚ Can we remove array elements?

28. Assignment 12
Sieve of Eratosthenes:-
⮚ Can we remove array elements?
We cannot remove array elements

29. Assignment 12
Sieve of Eratosthenes:-
⮚ Can we remove array elements?
We cannot remove array elements
⮚What can be done?

30. Assignment 12
Sieve of Eratosthenes:-
⮚ Can we remove array elements?
We cannot remove array elements
⮚What can be done?
Make it as 0

31. Assignment 12
Sieve of Eratosthenes:-
⮚ Can we remove array elements?
We cannot remove array elements
⮚What can be done?
Make it as 0
2 3 0 5 0 7 0 9 0 11 0 13 0 15 0 17 0 19 0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

32. Assignment 12
Sieve of Eratosthenes:-
⮚The next number in the list is 3, make multiples of 3 as 0
2 3 0 5 0 7 0 9 0 11 0 13 0 15 0 17 0 19 0
i
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

33. Assignment 12
Sieve of Eratosthenes:-
⮚ The next number in the list is 3, make multiples of 3 as 0
2 3 0 5 0 7 0 0 0 11 0 13 0 15 0 17 0 19 0
i
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

34. Assignment 12
Sieve of Eratosthenes:-
⮚ The next number in the list is 3, make multiples of 3 as 0
2 3 0 5 0 7 0 0 0 11 0 13 0 0 0 17 0 19 0
i
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

35. Assignment 12
Sieve of Eratosthenes:-
⮚The next number which is not removed is 5.
2 3 0 5 0 7 0 0 0 11 0 13 0 0 0 17 0 19 0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
i

36. Assignment 12
Sieve of Eratosthenes:-
⮚ The next number which is not removed is 5.
⮚It is not necessary to remove multiples of 5, because all non
prime numbers has been removed.
2 3 0 5 0 7 0 0 0 11 0 13 0 0 0 17 0 19 0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
i

37. ⮚Print all the non-zero numbers from the list.
Assignment 12
Sieve of Eratosthenes:-
2 3 0 5 0 7 0 0 0 11 0 13 0 0 0 17 0 19 0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

38. ⮚Prime numbers are:
2, 3, 5, 7, 11, 13, 17, 19
Assignment 12
Sieve of Eratosthenes:-

39. Assignment 12
Example’s:

40. Assignment 12
Example’s:
⮚Input:

41. Assignment 12
Example’s:
⮚Input: num = 20

42. Assignment 12
Example’s:
⮚Input: num = 20
Output:

43. Assignment 12
Example’s:
⮚Input: num = 20
Output: 2, 3, 5, 7, 11, 13, 17, 19

44. Assignment 12
Example’s:
⮚Input: num = 20
Output: 2, 3, 5, 7, 11, 13, 17, 19
⮚Input:

45. Assignment 12
Example’s:
⮚Input: num = 20
Output: 2, 3, 5, 7, 11, 13, 17, 19
⮚Input: num = 30

46. Assignment 12
Example’s:
⮚Input: num = 20
Output: 2, 3, 5, 7, 11, 13, 17, 19
⮚Input: num = 30
Output:

47. Assignment 12
Example’s:
⮚Input: num = 20
Output: 2, 3, 5, 7, 11, 13, 17, 19
⮚Input: num = 30
Output: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29

48. Assignment 12
Example’s:
⮚Input: num = 20
Output: 2, 3, 5, 7, 11, 13, 17, 19
⮚Input: num = 30
Output: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29
⮚Input:

49. Assignment 12
Example’s:
⮚Input: num = 20
Output: 2, 3, 5, 7, 11, 13, 17, 19
⮚Input: num = 30
Output: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29
⮚Input: num = -20

50. Assignment 12
Example’s:
⮚Input: num = 20
Output: 2, 3, 5, 7, 11, 13, 17, 19
⮚Input: num = 30
Output: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29
⮚Input: num = -20
Output:

51. Assignment 12
Example’s:
⮚Input: num = 20
Output: 2, 3, 5, 7, 11, 13, 17, 19
⮚Input: num = 30
Output: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29
⮚Input: num = -20
Output: Please enter a positive number which is > 1

52. Sample execution:-
Assignment 12

53. Sample execution:-
Assignment 12

54. Sample execution:-
Assignment 12

55. Assignment 12
Pre-requisites:-

56. Assignment 12
Pre-requisites:-
⮚Loops

57. Assignment 12
Pre-requisites:-
⮚Loops
⮚Operators

58. Assignment 12
Pre-requisites:-
⮚Loops
⮚Operators
⮚Arrays

59. Assignment 12
Pre-requisites:-
⮚Loops
⮚Operators
⮚Arrays
Objective:-

60. Assignment 12
Pre-requisites:-
⮚Loops
⮚Operators
⮚Arrays
Objective:-
⮚To understand the concept of if-else constructs and arrays.

61. Team Emertxe
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