Weekly Challenge 198

Two relatively straight forward tasks to start the new year.

Challenge, My solutions

Task 1: Max Gap

Task

You are given a list of integers, @list.

Write a script to find the total pairs in the sorted list where 2 consecutive elements has the max gap. If the list contains less then 2 elements then return 0.

My solution

For this task, I have defined two variables. The value gap records the largest gap between two numbers so far, while the count value records the number of occurrences of the gap.

The first thing I do is (numerically) sort the list. I then iterate from 0 to the size of the list minus two. For each iteration, I compare the difference in the value in that position to the one in the next position. If the gap is greater, I set gap to the difference, and reset count to 1. If the difference is the same as the current gap, I increase 1 to count.

Finally I display the value of count.

Examples

$ ./ch-1.py 2 5 8 1
2

$ ./ch-1.py 3
0

Task 2: Prime Count

Task

You are given an integer $n > 0.

Write a script to print the count of primes less than $n.

My solution

Time to pull out my trusty is_prime method. This was last used in task 2 from challenge 177. I iterate from 1 to n-1 and added one to count if that number is a prime. Then I display the value of count.

Examples

$ ./ch-2.py 10
4

$ ./ch-2.py 15
6

$ ./ch-2.py 1
0

$ ./ch-2.py 25
9