Consider a small circular linked list. How to detect the presence of cycles in this list effectively?
Anonymous Quiz
31%
Keep one node as head and traverse another temp node till end to check if its ‘next points to head
45%
Have fast and slow pointers with fast pointer advancing two nodes at a time
8%
Cannot determine, you have to pre-define if the list contains cycles
16%
Circular linked list itself represents a cycle. So no new cycles cannot be generated
Explanation:
Advance the pointers in such a way that the fast pointer advances two nodes at a time and slow pointer advances one node at a time and check to see if at any given instant of time if the fast pointer points to slow pointer or if the fast pointer’s ‘next’ points to the slow pointer. This is applicable for smaller lists.
Advance the pointers in such a way that the fast pointer advances two nodes at a time and slow pointer advances one node at a time and check to see if at any given instant of time if the fast pointer points to slow pointer or if the fast pointer’s ‘next’ points to the slow pointer. This is applicable for smaller lists.
Why does the name of JavaScript and Java are similar?
Anonymous Quiz
18%
JavaScript is a stripped-down version of Java.
39%
The syntax of JavaScript is loosely based on the syntax of Java.
9%
JavaScript and Java both are originated on the island of Java.
33%
None of the above
Which of the following real world scenarios would you associate with a stack data structure?
Anonymous Quiz
74%
piling up of chairs one above the other
13%
people standing in a line to be serviced at a counter
6%
offer services based on the priority of the customer
6%
tatkal Ticket Booking in IRCTC
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Explanation:
Stack follows Last In First Out (LIFO) policy. Piling up of chairs one above the other is based on LIFO, people standing in a line is a queue and if the service is based on priority, then it can be associated with a priority queue. Tatkal Ticket Booking Follows First in First Out Policy. People who click the book now first will enter the booking page first.
Stack follows Last In First Out (LIFO) policy. Piling up of chairs one above the other is based on LIFO, people standing in a line is a queue and if the service is based on priority, then it can be associated with a priority queue. Tatkal Ticket Booking Follows First in First Out Policy. People who click the book now first will enter the booking page first.
👍1
Sorry I've forwarded it wrong, here is a complete post:
image_2025-01-31_16-39-23.png
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Common Data Structure Operations and
Array Sorting Algorithms
Array Sorting Algorithms
It could be useful to have it as a cheat sheet
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SC15.png
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SQL EXECUTION ORDER
SQL Doesn’t Run the Way You Think It Does!
Most people assume SQL runs top to bottom—
but in reality, the database follows a completely different process.
Here’s what actually happens when you hit Run:
🔹 FROM & JOIN – First, SQL figures out where to pull the data from.
🔹 WHERE – Then, it filters out rows that don’t match your conditions.
🔹 GROUP BY – If needed, it groups the remaining rows together.
🔹 HAVING – Now, it filters those groups (not individual rows).
🔹 SELECT – Finally, it picks the columns you asked for.
🔹 ORDER BY – It sorts the result.
🔹 LIMIT – At the very end, it restricts the output.
Why does this matter?
⤷ You can’t use column aliases in WHERE
because SELECT runs later.
⤷ Filtering after grouping (HAVING)
is less efficient than filtering before (WHERE).
⤷ Understanding this helps you write faster, better queries.
Most analysts assume SQL reads queries like English.
✅ But databases have their own logic—and mastering it makes
you a 10x better analyst!
SQL Doesn’t Run the Way You Think It Does!
Most people assume SQL runs top to bottom—
but in reality, the database follows a completely different process.
Here’s what actually happens when you hit Run:
🔹 FROM & JOIN – First, SQL figures out where to pull the data from.
🔹 WHERE – Then, it filters out rows that don’t match your conditions.
🔹 GROUP BY – If needed, it groups the remaining rows together.
🔹 HAVING – Now, it filters those groups (not individual rows).
🔹 SELECT – Finally, it picks the columns you asked for.
🔹 ORDER BY – It sorts the result.
🔹 LIMIT – At the very end, it restricts the output.
Why does this matter?
⤷ You can’t use column aliases in WHERE
because SELECT runs later.
⤷ Filtering after grouping (HAVING)
is less efficient than filtering before (WHERE).
⤷ Understanding this helps you write faster, better queries.
Most analysts assume SQL reads queries like English.
✅ But databases have their own logic—and mastering it makes
you a 10x better analyst!
👍4