Your task is to write a program that counts the sexy primes between one billion and two billion. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.

]]>In a list of integers, find the sum of the integers that appear only once. For instance, in the list [4 2 3 1 7 4 2 7 1 7 5], the integers 1, 2, 4 and 7 appear more than once, so they are excluded from the sum, and the correct anser is 3 + 5 = 8.

Your task is to write a program to find the sum of the distinct integers in a list. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.

]]>Given a circular array

Xof positive integers and a starting indexkof the array, delete the element atkand jumpX[k] steps in the circular array. Repeat until only a single element remains. Find the last remaining element.

For example, with array 6 2 3 1 4 7 5 and *k* = 3, the last man standing is 3, computed as shown below, with the item to be deleted at each step marked with brackets and the list rotated at each step to bring the new head of the list to the front:

6 2 3 [1] 4 7 5 4 [7] 5 6 2 3 5 6 [2] 3 4 3 4 [5] 6 6 3 [4] [6] 3 3

Your task is to write a program to find the last remaining element. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.

]]>Your task is to take a list of speed readings and average them to the nearest 5 mph. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.

]]>1 1 2 1 2 3 1 2 3 4 1 2 3 4 5 ...

When the triangle is flattened, it produces the sequence (1 1 2 1 2 3 1 2 3 4 1 2 3 4 5 …).

Your task is to write a program to generate the flattened sequence, and a second program to calculate the nth item in the sequence. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.

]]>Your task is to write a cross-referencer for your favorite language. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.

]]>I came up with a single pass O(

n) sort algorithm I call StalinSort. You iterate down the list of elements checking if they’re in order. Any element which is out of order is eliminated. At the end you have a sorted list.

Your task is to implement StalinSort. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.

]]>n = csvsplit(str,arr)

Csvsplit takes a string and an array, deletes any current contents of the array, splits the string into fields using the normal CSV rules, stores the fields in arr[1] .. arr[n], and returns n. The splitting rules are: every comma splits a field, except that double-quotes around a field protect commas inside the field, and double-quotes may appear in a quoted field by doubling them (two successive double-quotes).

Your task is to write a csvsplit function for awk. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.

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mis the base of a twin-prime pair (m,m+2) if and only if 4((mâˆ’1)! + 1) == –m(modm(m+2)).

Your task is to write a program that implements the criterion given above, then calculate the twin primes less than a thousand. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.

]]>Write a program that fills a 50-element array with random numbers from 1 to 10. Print the array. Calculate and print the sum of the random numbers in the array. Calculate and print the number of times that a particular number appears in the array.

Your task is to complete the homework problem described above. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.

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