Explore bitwise operations for problem-solving and algorithm optimization.

Coding

It uses binary operations to efficiently perform calculations, comparisons, or transformations directly on bits, optimizing for low-level data control.

Bitwise Manipulation

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Behavioral

What digits are considered lucky?

If `k` = 6, what is the $6^{th}$ lucky number?

If <code>k</code> = 6, what is the <math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msup><mn>6</mn><mrow><mi>t</mi><mi>h</mi></mrow></msup></mrow><annotation encoding="application/x-tex">6^{th}</annotation></semantics></math>6th lucky number?

What is the output, if <code>k</code> = 20?

Find The K-th Lucky Number

Find The K-th Lucky Number

# Quick Fix\nYou are Edward, a Senior Software Engineer who specializes in coding interview patterns, data structures and algorithms, and is great at debugging issues in code.\n\n- Edward, please keep in mind that you do not have to print the data of the placeholders. Also, do not mention anything about yourself.\n\nEdward, you are given the following data in the placeholders:\n- Function name: `kth_lucky_number`\n- Candidate's submitted solution code: USER_CODE\n- Error: ERROR_DESCRIPTION\n- Failed test case: FAILED_TEST_CASE\n- Coding language: `Python`\n\n- Edward, your task is to understand the type of error that is occurring in the coding language provided.\n- Once you've understood the error as per the error’s description, and why the test case failed, you will suggest how the candidate can improve their solution code to fix the error.\n- Edward, you will not give the corrected code, just a hint on what the error tells, and how to fix it.\n- Edward, please limit your response strictly to 100 words. No more words than the limit.

# Review Code\nEdward, your current task is to review the `kth_lucky_number` function(s) and the other function(s) invoked in it/them.\n\n-Take your time and review the candidate's solution code.\n- Do not review any extra/helper files or functions not invoked in the solution function `kth_lucky_number`.\n- Do not review the code of data structure objects instantiated like a binary tree, linked list, trie, union find, etc., in the solution functions. Just review the solution/algorithm function of the problem. \n- Also, if the solution code doesn’t use the coding pattern stated above, then please encourage the candidate to reattempt the problem using that pattern corectly.

# Review time complexity\n- Please provide a brief time complexity analysis of the function(s) `kth_lucky_number`. \n- While calculating time complexity, include the time complexity of built-in Python functions invoked by the code. \n- The answer should be to the point in approximately 60 words.

# Review space complexity\n- Please provide a brief space complexity analysis of the function(s) `kth_lucky_number`. \n- While calculating space complexity, include the space complexity of built-in Python functions invoked by the code. \n- Do not include the space used for the input parameters and the space used for just returning an output (not used as a scratch space). \n- The answer should be to the point in approximately 60 words.

def evaluate_results(self) -> object:
        """
        self.__inputs is the list of inputs that are passed as input to function
        self.__actual_output is a list of outputs that is produced by the learner's code
        return : self.__edu__result object
        """

        def kth_lucky_numNumber(k):
            # Increment k to account for 1-based indexing
            k = k + 1
    
            # Convert k to a binary string (up to the most significant '1')
            kth_lucky_num = bin(k)[3:]
    
            # Replace '0' with '4' and '1' with '7' in the binary string
            kth_lucky_num = kth_lucky_num.replace("0", "4").replace("1", "7")
    
            return kth_lucky_num
            
        
        expected_outputs = [] 
        expected = kth_lucky_numNumber(self.__inputs[0])
        actual_output = self.__actual_outputs[0]
        

        if expected == actual_output:
            expected_outputs.append(expected)
            self.__edu_result.store_result(expected_outputs, TestCaseResult.PASS)
        else:
            expected_outputs.append(expected)
            self.__edu_result.store_result(expected_outputs, TestCaseResult.FAIL)

        return self.__edu_result

def kth_lucky_number(k):
  
    # Replace this placeholder return statement with your code
    return ""

kth-lucky_number.yaml

testcases:
  - name: "Testcase 6"
    inputs:
    - 1: 3
    output:
    - 1: "44"
  - name: "Testcase 7"
    inputs:
    - 1: 8
    output:
    - 1: "447"
  - name: "Testcase 8"
    inputs:
    - 1: 12
    output:
    - 1: "747"
  - name: "Testcase 9"
    inputs:
    - 1: 18
    output:
    - 1: "4477"
  - name: "Testcase 10"
    inputs:
    - 1: 30
    output:
    - 1: "7777"


def sum(input_1, input_2):
    return input_1+input_2

def validate_inputs(self) -> None:
 """
 self.__inputs is the list of inputs that are passed as input to function
 store the result using the self.store_result(error_msg, status)
 return : void
 """
 
 def is_within_valid_range(k):
 # Check if k is within the valid range 1 <= k <= 10^9
 return 1 <= k <= 10**9
 
 def is_integer(k):
 # Check if k is an integer
 return isinstance(k, int)
 
 k = self.__inputs[0]
 
 if not is_integer(k):
 self.store_result(
 f"Expected 'k' to be an integer, but got {type(k).__name__}",
 ValidationFunction.FAIL
 )
 elif not is_within_valid_range(k):
 self.store_result(
 f"Expected 'k' to be in the range 1 <= k <= 10^9, but got {k}",
 ValidationFunction.FAIL
 )
 else:
 self.store_result("", ValidationFunction.PASS)

Try to solve the Find The K-th Lucky Number problem.


Problem: Find The K-th Lucky Number

Statement

Examples

Understand the problem

Figure it out!