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Behavioral

What is the output given the following inputs?


["NumArray", "sumRange"]

[[[-2, 0, 3, -5, 2, -1]], [0, 2]]

What is the output given the following inputs?
[“NumArray”, “sumRange”]
[[[-2, 0, 3, -5, 2, -1]], [0, 2]]

What is the output given the following inputs?


["NumArray", "sumRange", "sumRange"]

[[[-2, 0, 3, -5, 2, -1]], [1, 4], [0, 3]]

What is the output given the following inputs?
[“NumArray”, “sumRange”, “sumRange”]
[[[-2, 0, 3, -5, 2, -1]], [1, 4], [0, 3]]

What is the output given the following inputs?


["NumArray", "sumRange"]

[[[-2, 0, 3, -5, 2, -1]], [2, 5]]

What is the output given the following inputs?
[“NumArray”, “sumRange”]
[[[-2, 0, 3, -5, 2, -1]], [2, 5]]

Range Sum Query - Immutable

Range Sum Query - Immutable

class NumArray:

    def __init__(self, nums):
        """
        :type nums: List[int]
        """
        

    def sum_range(self, left, right):
        """
        :type left: int
        :type right: int
        :rtype: int
        """

# 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: `__init__, sum_range`\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 `__init__, sum_range` 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 `__init__, sum_range`.\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) `__init__, sum_range`. \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) `__init__, sum_range`. \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.

TwoDArray

import sys
import json

sys.path.append("../ds_v1")
from data_structure import DataStructure

# throw parsing errors for incorrect test case format
def parsingError(element_string, error_message):
    sys.stderr.write(f"Parsing Error: {element_string} {error_message}")
    exit()


# className: MyCustomDS
class TwoDArray(DataStructure):
    def __init__(self):
        # constructor
        pass

    def __str__(self):
        # override print() for your data structure
        pass

    # return value will be passed to user program
    def construct(self, value: str, type_of_arr: int) -> any:
        # parse test case in json string 'value' to your desired data structure
        parse_list = json.loads(value)
        return parse_list

    # input param contains return value of user program
    def traverse(self, input: any, type_of_arr: int) -> str:
        # TwoDArray your data structure 'input' to a json string representing a test case output
        return json.dumps(input)


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
        """
        class NumArray:
            def __init__(self, nums):
                # Initialize the sum array with an extra space to handle prefix sums easily
                self.sum = [0] * (len(nums) + 1)
                
                # Compute the prefix sum array
                for i in range(len(nums)):
                    self.sum[i + 1] = self.sum[i] + nums[i]
        
            def sum_range(self, i, j):
                # Return the sum of the elements between indices i and j inclusive
                return self.sum[j + 1] - self.sum[i]
        
        def main(input_1, input_2):
            result = []
            trie_obj = NumArray(input_2[0][0])
            result.append(None)
            for i in range(1, len(input_1)):
                if input_1[i] == "sumRange":
                    res = trie_obj.sum_range(input_2[i][0], input_2[i][1])
                    result.append(res)
                

            return result

        # multiple outputs will be added at each index respectively for a single test_case
        expected_outputs = []
        inp1 = self.__inputs[0]
        inp2 = self.__inputs[1]
        expected = main(inp1 , inp2)

        # store the 1st expected output that should be displayed to the user 
        expected_outputs.append(expected)
        actual = self.__actual_outputs[0]

        if json.dumps(expected) == json.dumps(actual):
            self.__edu_result.store_result(expected_outputs, TestCaseResult.PASS)
        else:
            self.__edu_result.store_result(expected_outputs, TestCaseResult.FAIL)

        return self.__edu_result


from NumArray import *


def main(input_1, input_2):
    result = []
    trie_obj = NumArray(input_2[0][0])
    result.append(None)
    for i in range(1, len(input_1)):
        if input_1[i] == "sumRange":
            res = trie_obj.sum_range(input_2[i][0], input_2[i][1])
            result.append(res)
        

    return result

num_array_test_cases.yaml

testcases:
  - name: "testcase 1"
    inputs:
      - 1 : ["NumArray", "sumRange", "sumRange", "sumRange"]
      - 2 : [[[1, 2, 3, 4, 5]], [1, 3], [0, 2], [0, 4]]
    output:
      - 1 : [null, 9, 6, 12]
  - name: "testcase 2"
    inputs:
      - 1 : ["NumArray", "sumRange"]
      - 2 : [[[10, 20, 30, 40]], [1, 3]]
    output:
      - 1 : [null, 90]
  - name: "testcase 3"
    inputs:
      - 1 : ["NumArray", "sumRange", "sumRange", "sumRange"]
      - 2 : [[[10, -3, 5, 6, 8, -2]], [1, 4], [0, 3], [2, 5]]
    output:
      - 1 : [null, 16, 18, 17]
  - name: "testcase 4"
    inputs:
      - 1 : ["NumArray", "sumRange", "sumRange"]
      - 2 : [[[1000, 2000, 3000, 4000]], [1, 3], [0, 3]]
    output:
      - 1 : [null, 9000, 10000]




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_valid_1d_array_str(arr):
 """Check if the input is a valid 1D array of strings."""
 if not isinstance(arr, list):
 return False
 if any(elem is None or isinstance(elem, bool) for elem in arr):
 return False
 if not all(isinstance(elem, str) for elem in arr):
 return False
 return True
 def is_valid_1d_array_int(arr):
 """Check if the input is a valid 1D array of strings."""
 if not isinstance(arr, list):
 return False
 if any(elem is None or isinstance(elem, bool) for elem in arr):
 return False
 if not all(isinstance(elem, int) for elem in arr):
 return False
 return True

 def is_valid_2d_array(arr):
 """Check if the input is a valid 2D array of strings."""
 if not isinstance(arr, list):
 return False
 for sublist in arr:
 if not isinstance(sublist, list):
 return False
 if not is_valid_1d_array_int(sublist):
 return False
 return True

 def check_lengths(array_1, array_2):
 # Extract subarrays starting from the first index
 subarray_1 = array_1[1:]
 subarray_2 = array_2[1:]
 
 # Check if lengths are the same
 return len(subarray_1) == len(subarray_2)

 

 def check_sum_range(operation):
 return all(op == "sumRange" for op in operation[1:])

 def check_array(calls):
 return is_valid_2d_array(calls)

 def check_first_array_word_length(arr):
 first_array = arr[0]
 return all(1 <= len(word) <= 10 for word in first_array)

 def check_subsequent_arrays_length(arr):
 return all(len(sub_array) == 2 for sub_array in arr[1:])

 def check_pairs_condition(input_list):
 for sublist in input_list[1:]:
 # Ensure sublist is a flat list of size 2
 if len(sublist) != 2:
 raise ValueError("Each sublist after the first must contain exactly two elements.")
 
 # Unpack and check the pair
 i, j = sublist
 if i > j or j >= len(input_list[0][0]):
 return False
 return True
 
 operation = self.__inputs[0]
 calls = self.__inputs[1]

 # Validate operation array
 if not is_valid_1d_array_str(operation):
 self.store_result("'operation' should be a valid 1D array of strings in the following format: ['NumArray','sum_range','sum_range'...]", ValidationFunction.FAIL)
 elif operation[0] != "NumArray":
 self.store_result("'operation[0]' should have the value: 'NumArray'", ValidationFunction.FAIL)
 elif not check_sum_range(operation):
 self.store_result("'operation[1:]' should have the value: 'sum_range'", ValidationFunction.FAIL)
 # Validate calls array
 elif not is_valid_2d_array(calls[0]):
 self.store_result("'calls' should be a valid 2D array of int", ValidationFunction.FAIL)
 elif not 1 <= len(calls[0][0]) <= 1000:
 self.store_result("'1st array' length should be in the range [1, 1000]", ValidationFunction.FAIL)
 elif not check_subsequent_arrays_length(calls):
 self.store_result("'query' length should be exactly 2", ValidationFunction.FAIL)
 elif not check_lengths(operation, calls):
 self.store_result("Number of operations should be equal to number of calls", ValidationFunction.FAIL)
 elif not check_pairs_condition(calls):
 self.store_result(f"i <= j < {len(calls[0][0])} should be True", ValidationFunction.FAIL)
 else:
 self.store_result("", ValidationFunction.PASS)

Try to solve the Range Sum Query - Immutable problem.

Problem: Range Sum Query - Immutable

Statement

Examples

Understand the problem

Figure it out!