Some Algorithms

This repo is about algorithms and solutions that I made. You can examine my solutions to these algorithms that I come across. If there are any questions you want me to solve, please let me know.

1) Even Pair: (Medium)

Program that returns True if 2 numbers are even in consecutive numbers in the given string expression.

Examples:

• "hy361jpa68" -> True, because 6 and 8 is even.
• "75khs34qas98wlk" -> False.
• "411sd95sl436kdg5fh4" -> True, because 4 and 6 is even in 436.

2) Array Couples (Inverted Pairs): (Hard)

This program looks for pairs with 2 in a given array and if the inverse of the corresponding pair is found, it deletes it from the array.

Examples:

• [4, 5, 1, 4, 5, 4, 4, 1] -> prints "yes", because all pairs have an reversed form in the array.
• [6, 2, 2, 6, 5, 14, 14, 1] -> prints "5, 14, 14, 1", because '5, 14' and '14, 1' don't have a reversed form.
• [2, 1, 1, 2, 30, 50] -> prints "30, 50", because '30, 50' has no reversed form

3) Flatten List: (Medium)

Write a function that flattens a list. Its elements can consist of multi-layered lists (such as [[3], 2]) or non-scalar data.

Example:

• [[1, 'a', ['cat'], 2], [[[3]], 'dog'], 4, 5] -> [1, 'a', 'cat', 2, 3, 'dog', 4, 5]

4) Reverse List: (Medium)

Write a function that reverses the elements inside the given list. If the elements inside the list also contain the list, reverse their elements as well.

Examples:

• [[1, 2], [3, 4], [5, 6, 7]] -> [[7, 6, 5], [4, 3], [2, 1]]
• [["a", ["b", "c"]], ["123", 123, [456, 789]]] -> [[[789, 456], 123, '123'], [['c', 'b'], 'a']]

5) Counting Minutes: (Medium)

Function that finds the total minutes in a given time interval in hours.

Examples:

• "9:00am-10:00am" -> 60
• "1:00pm-11:00am" -> 1320

6) Knight Jumps: (Hard)

A function that returns the number of positions the knight can go if there are no other pieces on a standard chessboard. The current position of the horse will be given as ("x y").

Examples:

• "(1 1)" -> 2
• "(7 6)" -> 6
• "(3 3)" -> 8

7) Fibonacci Checker: (Medium)

Program that returns "yes" if the given number is in the Fibonacci sequence, and "no" if it is not.

Examples:

• Input: 34 -> Output: yes
• Input: 54 -> Output: no

8) Nearest Smaller Values: (Medium)

This program compares the elements in a given array in order and prints the lesser or equal number. If there is no element smaller than itself, it adds -1 instead.

Examples:

• Input: [5, 2, 8, 3, 9, 12] -> Output: -1, -1, 2, 2, 3, 9
• Input: [5, 3, 1, 9, 7, 3, 4, 1] -> Output: -1, -1, -1, 1, 1, 1, 3, 1

9) Line Ordering: (Hard)

This program prints how many different ways people can be in a queue with the rules given as a list.

Examples:

• Input: ["A>B", "A<C", "C<Z"] -> Output: 1 -> ZCAB
• Input: ["A>B", "B<R", "R<G"] -> Output: 3 -> GRAB, GARB, AGRB

10) Blackjack Highest: (Hard)

Function that prints whether the cards in the given list are blackjack and prints the highest card.

Examples:

• Input: ["four", "ace", "ten"] -> Output: below ten
• Input: ["ace", "queen"] -> Output: blackjack ace
• Input: ["queen", "king", "jack"] -> Output: above king

11) Sudoku Quadrant Checker: (Hard)

A function that finds whether the given statements on a 9x9 sudoku board are true or false. If there is a repeating number, you should print this incorrect cell on the screen.

Examples:

• Input: (You can see the sudoku list in code) -> Output: 1, 3, 4

12) Prime Time: (Easy)

Program that checks if the given number is prime. It prints "true" if the number is prime, "false" otherwise.

Examples:

• Input: 1 -> Output: false
• Input: 2 -> Output: true
• Input: -3 -> Output: false

13) Gas Station: (Hard)

A program that will calculate whether you can return to the starting point by wandering around the gas stations on a route given by Array. If the route is completing, print the smallest index, if not, print "impossible".

Examples:

• Input: ["4", "1:1", "2:2", "1:2", "0:1"] -> Output: impossible
• Input: ["5", "1:1", "2:2", "1:2", "0:1", "6:3"] -> Output: 5
• Input: ["5", "4:1", "2:2", "1:2", "0:1", "6:3"] -> Output: 1