Here's a challenge — try to solve the following 5 Python programming puzzles WITHOUT googling for the answer.

1) Magic Square

A magic square is a 3x3 grid containing the numbers 1 to 9. Every 3 consecutive numbers (row, column or diagonal) must add up to 15. Here's a valid magic square

[  [2, 7, 6],
   [9, 5, 1],
   [4, 3, 8]  ]

In this puzzle, you are given an incomplete magic square.

[  [2, 0, 0],
   [0, 0, 0],
   [0, 3, 8]  ]

Magic squares are not supposed to have 0's. Here, a 0 means that you need to fill it in with a number between 1 and 9.

• Each number from 1 to 9 can only appear once
• Every row, column and diagonal of 3 numbers MUST add up to 15

def solve(incomplete_square):
    # CODE HERE
square = [  
    [2, 0, 0],
    [0, 0, 0],
    [0, 3, 8]
]
solve(square)
# [  [2, 7, 6],
#    [9, 5, 1],
#    [4, 3, 8]  ]

2) Uppercasing A Screwed Up Dictionary

You are given a messy screwed up dictionary with multiple unstructured layers of nesting. For instance:

d = {
    "a": {"b":"c"},
    "d": {
        "e":"f",
        "g": {
            "h":"i",
            "j":"k",
            "l":"m"
        },
        "n": {
            "o": {
                "p": {
                    "q": {"r":"s"}
                }
            }
        }
    }
}

Write a function that takes in this screwed up dictionary, and returns a COPY of this dictionary where all keys and values are converted into uppercase.

d = {
    "A": {"B":"C"},
    "D": {
        "E":"F",
        "G": {
            "H":"I",
            "J":"K",
            "L":"M"
        },
        "N": {
            "O": {
                "P": {
                    "Q": {"R":"S"}
                }
            }
        }
    }
}

3) Dictionary From String

You are given a string representing a dictionary.

string = '{"name":"rocky", "age":5, "imported":True}'

Assume that key-value pairs are simple, and there are no nested lists, dictionaries and other collections. Values will simply be either numbers (in/float), strings, or booleans.

Without using the json library, the exec or eval functions, or any other built-in parsers, write a function that takes in this string, and returns an actual dictionary represented by the string.

4) Shortest Path In Maze

You are given a list of strings representing a maze.

maze = [
    "P#----",
    "-#-##-",
    "------",
    "-#-##-",
    "-#-#--",
    "---#-X",

• P represents the player
• - represents an empty space. The player can stand on the empty space
• # represents a wall. The player cannot stand on a wall
• X represents the objective. The player wins if he reaches the objective.

Write a function that takes in this maze, and returns the shortest path from the player to the objective. The player can only move one step at a time, and in only 4 directions — upwards, downwards, leftwards and rightwards. A sample of what the function returns:

["down", "down", "right", "right", "right", "right", "right", "down", "down", "down"]

5) Screwed Up Dictionary To Screwed Up List

Once again, you are given a messy screwed up dictionary with multiple levels of nesting.

d = {
    "a": "b",
    "c": "d",
    "e": {
        "f": "g",
        "h": "i"
    },
    "j": {
        "k": {
            "l": {"m":"n"}
        }
    }
}

Write a function to convert every single nested dictionary inside into a list. An example of the output:

d = [
    ["a", "b"],
    ["c", "d"],
    ["e", [
        ["f", "g"],
        ["h", "i"]
    ]],
    ["j", [
        "k", [
            "l", ["m", "n"]
        ]
    ]]
]

Conclusion

How many did you manage to solve? And how long did it take you?

Some Final words

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