Learn and practice the Greedy Techniques and Dynamic Programming patterns to solve coding interview problems.

Educative-77 in JavaScript: Accelerate Your Coding Interview Prep

This module teaches you two of the most important problem-solving techniques in the optimization domain: Greedy Techniques and Dynamic Programming. Not all problems require an exhaustive search through the solution space. Rather, consistently choosing the locally optimal solution can be proven to yield the globally optimal solution. In such situations, Greedy Techniques result in simple, highly efficient solutions. Other problems have a well-defined structure, where the same subproblem is encountered and solved multiple times. Dynamic Programming techniques allow us to compute once and reuse the solutions to recurring subproblems.

Optimization Techniques

# Statement

Given an array of integers called `nums`, each element represents a square in a game board. At each turn, the player can take up to $s$ steps toward the last square, where $s$ is the value of the current square. This means from any position, you can move forward by any number of steps from $1$ up to the value at that position. Starting at the first index, your goal is to determine whether it’s possible to reach the last index of the array. Write a function that returns TRUE if you can reach the end, or FALSE if you get stuck somewhere.

**Constraints**:

* $1 \leq$ `nums.length` $\leq 10^3$
* $0 \leq$ `nums[i]` $\leq 10^3$

Can you reach the end of [1, 2, 3, 4, 5] if you start from the very first element?

Can you reach the end of [1, 2, 3, 4, 5] if you start from the very first element?

Can you reach the end of [4, 2, 3, 1, 0] if you start from the very first element?

Can you reach the end of [4, 2, 3, 1, 0] if you start from the very first element?

Can you reach the end of [3, 0, 0, 0, 0] if you start from the very first element?

Can you reach the end of [3, 0, 0, 0, 0] if you start from the very first element?

Jump Game I

Jump Game I

Help me debug only the function Jump Game I . . I don't need the corrected code.I don't want explanations or code review. Just provide me the exact and to-the-point error that helps me run the code successfully on the test cases provided.

Please help me understand why this code failed for the last failed test case. Don't give me the corrected code. . If yes, then Just provide me the exact and to-the-point error that helps me run the code successfully on the test cases provided.

Your current task is to review only the jumpGame function and the other function(s) invoked in it/them. Do not review extra/helper files or functions not invoked in the solution function jumpGame. Do not review the code of data structures 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. Also, Answer the following questions: Is the Greedy Techniques pattern used? Take your time and review the code.

Please provide a brief time complexity analysis of the function jumpGame. While calculating time complexity, include the time complexity of built-in Javascript functions invoked by the code. The Answer should be to the point and in a few lines.

Please provide a brief Space complexity analysis of the function jumpGame. While calculating space complexity, include the space complexity of built-in Javascript functions invoked by the code. 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). The Answer should be to the point and in a few lines

def evaluate_results(self) -> object:
 def jump_game(nums):
 target_num_index = len(nums) - 1
 for i in range(len(nums) - 2, -1, -1):
 if target_num_index <= i + nums[i]:
 target_num_index = i

 if target_num_index == 0:
 return True
 return False
 """
 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
 """
 # multiple outputs will be added at each index respectively for a single test_case
 expected_outputs = [] 
 inp = self.__inputs[0]
 expected = jump_game(inp)
 # 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

function jumpGame(nums){
    // Replace this placeholder return statement with your code
    return false
}

export {jumpGame};

jump_game1.yaml

testcases:
  - name: "testcase 1"
    inputs:
    - 1 : [2, 3, 1, 1, 9]
    output: 
    - 1 : True
  - name: "testcase 2"
    inputs:
    - 1 : [3, 2, 1, 0, 4]
    output: 
    - 1 : False
  - name: "testcase 3"
    inputs:
    - 1 : [4, 0, 0, 0, 4]
    output: 
    - 1 : True
  - name: "testcase 4"
    inputs:
    - 1 : [0]
    output: 
    - 1 : True
  - name: "testcase 5"
    inputs:
    - 1 : [1]
    output: 
    - 1 : True

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(arr):
 if not isinstance(arr, list):
 return False # Not a valid 1D array if it's not a list
 
 return all(isinstance(elem, int) and not isinstance(elem, bool) for elem in arr)

 nums_array = self.__inputs[0]
 # inputs can be accessed using self.__inputs starting from 0 to len(self.__inputs) - 1
 if not is_valid_1d_array(nums_array):
 self.store_result(("Not a Valid 1D Integer Array."), ValidationFunction.FAIL)
 elif not all(0 <= num <= 1000 for num in nums_array):
 self.store_result ("'nums' must consist of values from 0 to 1000 only", ValidationFunction.FAIL)
 elif not (1 <= len(nums_array) <= 1000):
 self.store_result ("expected 'nums' to have 1 <= nums.length <= 1000", ValidationFunction.FAIL)
 else:
 self.store_result("", ValidationFunction.PASS)

Greedy Techniques

Dynamic Programming

Conclusion

Jump Game I

Statement

Examples

Understand the problem

Figure it out!

Try it yourself