# Problems

1 – 50 of 77
 Problem Title Likes Solvers Difficulty

#### Problem 5. Triangle Numbers

Created by: Cody Team

Tags math, triangle, nice

114

22732

#### Problem 26. Determine if input is odd

Created by: Cody Team

115

21339

#### Problem 6. Select every other element of a vector

Created by: Cody Team

161

26953

#### Problem 17. Find all elements less than 0 or greater than 10 and replace them with NaN

Created by: Cody Team

63

14468

#### Problem 76. De-dupe

Created by: Cody Team

Tags matlab

11

2394

#### Problem 35. Quote Doubler

Created by: Cody Team

9

2343

#### Problem 41. Cell joiner

Created by: Cody Team

Tags strings, matlab

31

4487

#### Problem 33. Create times-tables

Created by: Cody Team

Tags matrices

92

13515

#### Problem 14. Find the numeric mean of the prime numbers in a matrix.

Created by: Cody Team

Tags easy, matrices

43

7907

#### Problem 19. Swap the first and last columns

Created by: Cody Team

89

16500

#### Problem 30. Sort a list of complex numbers based on far they are from the origin.

Created by: Cody Team

23

4987

#### Problem 20. Summing digits

Created by: Cody Team

Tags strings, sum

33

6756

#### Problem 12. Fibonacci sequence

Created by: Cody Team

95

11717

#### Problem 32. Most nonzero elements in row

Created by: Cody Team

Tags matrices

37

6603

#### Problem 72. Interpolator

Created by: Cody Team

36

3107

#### Problem 21. Return the 3n+1 sequence for n

Created by: Cody Team

Tags 3n+1, sample

74

7233

#### Problem 10. Determine whether a vector is monotonically increasing

Created by: Cody Team

114

16284

#### Problem 9. Who Has the Most Change?

Created by: Cody Team

74

7960

#### Problem 22. Remove the vowels

Created by: Cody Team

Tags regexp, siam

23

5488

#### Problem 25. Remove any row in which a NaN appears

Created by: Cody Team

71

7777

#### Problem 4. Make a checkerboard matrix

Created by: Cody Team

190

14447

#### Problem 66. Find the two-word state names

Created by: Cody Team

Tags regexp, states

5

1010

#### Problem 62. Elapsed Time

Created by: Cody Team

Tags time

15

2324

#### Problem 40. Reverse Run-Length Encoder

Created by: Cody Team

Tags encoding

16

2077

#### Problem 39. Which values occur exactly three times?

Created by: Cody Team

Tags search

21

4486

#### Problem 73. Replace NaNs with the number that appears to its left in the row.

Created by: Cody Team

Tags matlab

16

2511

#### Problem 42. Find the alphabetic word product

Created by: Cody Team

Tags matlab

10

2795

#### Problem 87. Indexed Probability Table

Created by: Cody Team

Tags matlab

8

1828

#### Problem 44. Trimming Spaces

Created by: Cody Team

9

1896

#### Problem 28. Counting Money

Created by: Cody Team

Tags regexp, strings

14

2995

#### Problem 57. Summing Digits within Text

Created by: Cody Team

Tags strings

10

1937

#### Problem 94. Target sorting

Created by: Cody Team

Tags sorting, matlab

26

3935

#### Problem 50. QWERTY coordinates

Created by: Cody Team

Tags indexing

18

1963

#### Problem 46. Which doors are open?

Created by: Cody Team

25

2698

#### Problem 49. Sums with Excluded Digits

Created by: Cody Team

Tags strings

13

1710

#### Problem 77. Clean the List of Names

Created by: Cody Team

Tags strings

3

1263

#### Problem 60. The Goldbach Conjecture

Created by: Cody Team

Tags primes

56

4709

#### Problem 37. Pascal's Triangle

Created by: Cody Team

23

3565

#### Problem 23. Finding Perfect Squares

Created by: Cody Team

Tags sets

139

14446

#### Problem 13. Remove all the consonants

Created by: Cody Team

Tags regexp, basics

23

3665

#### Problem 16. Return the largest number that is adjacent to a zero

Created by: Cody Team

Tags vectors

25

4563

#### Problem 27. Pangrams!

Created by: Cody Team

Tags strings

33

3156

#### Problem 80. Test for balanced parentheses

Created by: Cody Team

Tags regexp, parens

9

1060

#### Problem 53. Duplicates

Created by: Cody Team

5

1740

#### Problem 74. Balanced number

Created by: Cody Team

Tags matlab

19

2431

#### Problem 51. Find the two most distant points

Created by: Cody Team

Tags distance

8

2217

#### Problem 47. Extract leading non-zero digit

Created by: Cody Team

5

1638

#### Problem 85. Remove the polynomials that have positive real elements of their roots.

Created by: Cody Team

Tags matlab

3

1152

#### Problem 48. Making change

Created by: Cody Team

Tags money, subs

15

2786

#### Problem 64. The Goldbach Conjecture, Part 2

Created by: Cody Team

Tags primes

16

1836

1 – 50 of 77