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Gaurav Deshpande gaurav9822

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@dideler
dideler / bitwise-operators.md
Created April 12, 2012 08:25
Bitwise tricks

Inspired by this article. Neat tricks for speeding up integer computations.

Note: cin.sync_with_stdio(false); disables synchronous IO and gives you a performance boost. If used, you should only use cin for reading input (don't use both cin and scanf when sync is disabled, for example) or you will get unexpected results.

Multiply by a power of 2

x = x << 1; // x = x * 2

@jboner
jboner / latency.txt
Last active July 20, 2026 13:24
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@rgreenjr
rgreenjr / postgres_queries_and_commands.sql
Last active June 4, 2026 21:14
Useful PostgreSQL Queries and Commands
-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
FROM pg_stat_activity
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
ORDER BY query_start desc;
-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query
FROM pg_stat_activity
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'
@KWMalik
KWMalik / interviewitems.MD
Created September 16, 2012 22:04 — forked from amaxwell01/interviewitems.MD
My answers to over 100 Google interview questions

##Google Interview Questions: Product Marketing Manager

  • Why do you want to join Google? -- Because I want to create tools for others to learn, for free. I didn't have a lot of money when growing up so I didn't get access to the same books, computers and resources that others had which caused money, I want to help ensure that others can learn on the same playing field regardless of their families wealth status or location.
  • What do you know about Google’s product and technology? -- A lot actually, I am a beta tester for numerous products, I use most of the Google tools such as: Search, Gmaill, Drive, Reader, Calendar, G+, YouTube, Web Master Tools, Keyword tools, Analytics etc.
  • If you are Product Manager for Google’s Adwords, how do you plan to market this?
  • What would you say during an AdWords or AdSense product seminar?
  • Who are Google’s competitors, and how does Google compete with them? -- Google competes on numerous fields: --- Search: Baidu, Bing, Duck Duck Go
@P7h
P7h / IntelliJ_IDEA__Perf_Tuning.txt
Last active October 16, 2025 02:52
Performance tuning parameters for IntelliJ IDEA. Add these params in idea64.exe.vmoptions or idea.exe.vmoptions file in IntelliJ IDEA. If you are using JDK 8.x, please knock off PermSize and MaxPermSize parameters from the tuning configuration.
-server
-Xms2048m
-Xmx2048m
-XX:NewSize=512m
-XX:MaxNewSize=512m
-XX:PermSize=512m
-XX:MaxPermSize=512m
-XX:+UseParNewGC
-XX:ParallelGCThreads=4
-XX:MaxTenuringThreshold=1
@raineorshine
raineorshine / java-exception-handling-best-practices.md
Last active May 19, 2024 10:57
5 Great Resources for Exception Handling Best Practices in Java

General Tip

"The trick is to catch exceptions at the proper layer, where your program can either meaningfully recover from the exception and continue without causing further errors, or provide the user with specific information, including instructions on how to recover from the error. When it is not practical for a method to do either of these, simply let the exception go so it can be caught later on and handled at the appropriate level."

Resources

Advantages of Exceptions
Excellent example of separating error-handling code from program logic

Three Rules for Effective Exception Handling
Longer explanation and case study of exception use, including the basic principles of "throw early" and "catch late". Clear and thorough.

@neomatrix369
neomatrix369 / PerformanceRelated.md
Last active April 9, 2026 17:10
Interesting links in the areas of HPC, low latency, mechanical harmony/sympathy, garbage collection
@tsiege
tsiege / The Technical Interview Cheat Sheet.md
Last active July 16, 2026 19:50
This is my technical interview cheat sheet. Feel free to fork it or do whatever you want with it. PLEASE let me know if there are any errors or if anything crucial is missing. I will add more links soon.

ANNOUNCEMENT

I have moved this over to the Tech Interview Cheat Sheet Repo and has been expanded and even has code challenges you can run and practice against!






\

@swenson
swenson / gist:cf74cd8e282443b43b8a
Created May 21, 2014 15:51
Google Interview Study Guide
Author unknown.
1.) Algorithm Complexity: You need to know Big-O. If you struggle with
basic big-O complexity analysis, then you are almost guaranteed not to
get hired.
For more information on Algorithms you can visit:
http://www.topcoder.com/tc?module=Static&d1=tutorials&d2=alg_index
2.) Coding: You should know at least one programming language really
well, and it should preferably be C++ or Java. C# is OK too, since
@staltz
staltz / introrx.md
Last active July 19, 2026 16:25
The introduction to Reactive Programming you've been missing