Top 3 Winners

 

Winner: Ruben Maxwell, Our Lady Queen of the World Catholic Academy, Richmond Hill, Canada

 

​​​​​1st ​​Runner-up: Jayden Jeswin Raj, Vels Vidyashram, Chennai

 

2nd Runner-Up: Ibrahim Naheek Hussain Nahid, Ahmadhiyya International School, Male, Maldives

Leaderboard Link to view your rank and points:

https://www.codingal.com/competitions/usaco-practice-battle-may24/leaderboard/

Codingal, the #1 online coding platform for kids and teens presents USA Computing Olympiad (USACO) Practice Battle for Grade 8-12 students.

What is United States of America Computing Olympiad (USACO)?

 

The United States of America Computing Olympiad (USACO) is the most prestigious pre-college level Computer Science competitions in the USA, which serves as qualification for the International Olympiad in Informatics (IOI) in the United States of America.

 

What is USA Computing Olympiad (USACO) Practice Battle?

 

USA Computing Olympiad Practice Battle is a monthly coding competition by Codingal which provides a robust platform for programmers preparing for the USACO competition. It will be held online every last Saturday of the month. 

 

 

Competition Format

 

• Virtual/Online competition
• 10 problems to be solved in 1.5 hours using either C, C++, Java, or Python.
• Each problem statement will have points associated with it.
• Points increase with the difficulty level of the problems.
• Real-time leaderboard. 
• The student with the highest points will be the winner.
• Winner will be announced immediately on the leaderboard.

 

Grade Eligibility: Grade 8-12

 

Competition Schedule

• Competition Date: May 25, 2024 
• Competition Time: 12:00 PM to 1:30 PM PDT

 

Judging

 

• All submissions are evaluated by an online judge. 
• The problems will be partially graded, which means, you will be awarded points for passing each test case. 
• There are no penalties for incorrect submissions. 
• Feel free to submit as many solutions as you like; amongst all your correct submissions, the best code will be considered. 

 

 

Steps to register for USA Computing Olympiad (USACO) Practice Battle May 2024

 

• Click on the "Register & Start" button on this page.
• Input your mobile number.
• Enter all the necessary information in the "Competition Registration Form".
• Click on the "Register for competition" button and you are registered for the competition.

 
How to enter the USA Computing Olympiad (USACO) Practice Battle May 2024 on May 25, 2024 at 12 PM PDT ?

 

• Register for the competition if you have not registered yet.
• If you are a registered user but logged out, click on the "Register Now" button to fill in your mobile number and grade. Verify your mobile number through an OTP received via email/ whatsapp.
• Click on the "Start Now" button on the competition day, i.e. May 25, 2024 at 12 PM. 
• Tap on it and start solving the problems.
• If you get logged out of the competition, you can log back in and resume from where you left off by clicking on Start Now button. Your progress is auto-saved.

1. Is this USACO Practice Battle online?

Yes, this competition is 100% online. Students can participate as long as they have access to a computer/laptop and an internet connection.

 

2. How much does it cost to enter into this competition?

There is no registration fee to participate in the competition.

 

3. What type of problems will be there?

There will be coding problems to solve using C, C++, Java, and Python. It will consist of 10 coding problems to be solved in 1.5 hours that will help you prepare for the USACO competition.

 

4. Can I participate in the competition using a mobile?

No. We don't support mobile devices yet for participating in the competition. We suggest you participate in the competition using a laptop/desktop.

 

5. What type of problems will I have to solve in this competition?

All problems in this competition will be coding problems.

• Write code in the online code editor that is provided with each problem and submit it.
• You can make multiple submissions. The platform automatically considers the best submission.

 

6. Are the programming problems restricted to specific languages?

The languages that you can write the code in are mentioned in the challenge details, if applicable.

 

7. What will happen in case there is an issue with my computer or Internet connection?

If there is an issue with your computer or your Internet connection, you will not lose your previously submitted answers. They will be saved on Codingal's servers. You can log in again and continue coding from where you left off. However, the timer will continue running, which is why it is advised that you ensure that your computer/Internet connection is working properly before you begin the challenge.

 

8. How do I Test & Submit my code?

Every problem has the following two buttons:

a. Test

• When you click Test, the code is tested against the sample input and output. You can provide your own custom input too.

• This ensures that you are able to test your code against predefined sample test cases before you submit your code.

b. Submit

When you click Submit, the code is checked extensively against internal test cases. The following parameters are considered while checking the code:

• Time limit: The code should run within the stipulated time otherwise, it will throw a Time Limit Exceeded (TLE) error.

• Memory limit: The code should run within the given memory size otherwise, it will throw a Memory Limit Exceeded (MLE) error.

• Errors during runtime: Specific test cases check for Runtime Errors (RE) only.

• Correct answer: If your answer is incorrect, then you will see the message Wrong Answer (WA) on the screen. This means that your program is not printing the correct answer. Ensure that your program conforms with the output format that is required.

 

9. Is it possible to change my submission after I have submitted my code?

Yes, you can edit and submit your code for a problem any number of times before the completion time window closes.

 

10. How does Codingal's evaluation engine determine whether my program is correct?

Codingal's evaluation engine is an automated code checker for every program and not a human being. The code checker tests your code automatically. Therefore, you must write your code accordingly.

For each problem, based on the specifications mentioned in the problem statement, there will be one or more input files and corresponding (correct) output files. The program that you create is run on each of the input files, and the corresponding output must match the (correct) output files in order.

Your program will be marked incorrect in the following cases:

• Output files (generated by running your code) do not match the pre-generated output files.

• Output files (generated by running your code) match all the pre-generated output files; however, it is not in the order in which the pre-generated output files are arranged.

 

11. How does the time limit work?

Your program must read, process, and output the result for all input files within the specified time limit.

The input file will be in the format that is specified in the problem. This means that if each input file contains multiple test cases, then your code must pass all the test cases within the specified time limit.

 

12. How does the total execution time work?

Your code is tested multiple times against different input files. The displayed execution time is the total time spent executing each input file. Hence, Total execution time <= (Time Limit * Number of input files)

Your program is terminated in the following scenarios:

• If the time that is required to execute each input file exceeds the time limit execution that is set for any input file.

• If the total time that is required to execute all the input files exceeds the total time limit allowed.

 

12. How does the total memory consumed work?

The total memory consumed by a program is the sum of the memory that is consumed by the program in stack, data, heap, and BSS. To understand more about the address space of a program and the memory consumed, refer to this explanation.

 

13. My program doesn't compile. Why?

• C/C++

  • Ensure that you are using an updated compiler that complies with the standards.

  • For example, do not use Turbo C++. Code that compiles in Turbo C++ will often not compile on the online judge.

  • Also, remove 'conio.h includes' in your code.

• Java

  • We support multiple classes and inner static classes.

  • Your code may throw errors if the inner classes are not static.

  • Please note that we will remove this constraint very soon. We will update you when this happens.

• Other languages

  • The compilation errors that you see on the screen are self-explanatory.

  • However, if you require any more information, please write your query in the comments or send us a chat message.

We recommend you write code directly in the code editor provided for every problem and not use the local compiler to run your code.

 

14. Does TLE error mean that my code is correct but slow?

No, Time Limit Exceeded or TLE means that your solution has exceeded the amount of time that is allowed for problem execution or for a specific test case. Your solution never finished running in time, and it was stopped in between. There is no definite way to know whether the code was correct.

 

15. What does Wrong Answer (WA) mean?

WA means that your program ran successfully but gave an incorrect answer. This could mean either of the following:

• Your program contains a bug.

• You have not interpreted the problem statement correctly.

Apart from the sample input, your code will also be evaluated against multiple input and output cases. Therefore, even if your code passes the sample input correctly, it may not have passed one of the other input and output cases.

 

16. What happens if I indulge in plagiarism?

We take cheating/plagiarism very seriously. You will be disqualified from the competition, and your account may be permanently blocked on Codingal.

 

17. Why is my submission queued?

Your submission is queued because of simultaneous submissions by multiple users. You will receive the result of your submission in real time as soon as it is processed. Please wait for some time to receive the result of your program.

 

18. When will I receive the results of the competition?

You can view your ranking on the leaderboard. This leaderboard is updated in real-time and you can see where you stand. However, the leaderboard stops updating 30 mins before the competition ends. 

 

19. Where can I view the solutions for the problems of this competition?

Once the competition is over, we will publish the solutions. Keep a watch on this page to view and download all the solutions.

 

20. Why do I see a runtime error when I submit my program?

A runtime error means that the program was compiled successfully, but it crashed or exited with an error. The most common error messages include the following:

 

S. No.	Error	Description	Reason
1	SIGSEGV	Segmentation fault error	Caused by an out-of-scope array index causing a buffer overflow, an incorrectly initialized pointer, etc. The signal is generated when a program tries to read or write outside the memory that is allocated for it, or to write memory that can only be read. For example, you are accessing a[-1] in a language that does not support negative indices for an array.
2	SIGXFSZ	Output limit exceeded error	Your program has printed too much data to output.
3	SIGFPE	Floating-point error	This usually occurs when you're trying to divide a number by 0, or trying to take the square root of a negative number.
4	SIGABRT	Raised by the program	This happens when the judge aborts your program in the middle of execution. This can also be raised due to insufficient memory.
5	NZEC	Non-zero exit code error	This message means that the program exited the shell by returning a value that is different from 0. For languages such as C/C++, this probably means you forgot to add "return 0" at the end of the program. It could happen if your program threw an exception that was not caught. Trying to allocate too much memory in a vector. For interpreted languages like Python, NZEC will usually mean that your program either crashed or raised an uncaught exception. Some of the reasons being in such cases would be the runtime errors mentioned above. Or, for instance, usage of an external library which is causing some error, or not being used by the judge.
6	MLE	Memory limit exceeded error	This error means that your program tried to allocate memory beyond the memory limit indicated. This can occur if you declare a very large array, or if a data structure in your program becomes too large.
7	OTHER	Generated when you use too much memory	Check for arrays that are too large or other elements that could grow to a size too large to fit in memory. Sometimes it can also be generated for reasons similar to the SIGSEGV error.

 

26. How do I avoid runtime errors?

• Ensure that you are not using variables that haven't been initialized. These may be set to 0 on your computer but aren't guaranteed to be on the judge.

• Check every single occurrence of accessing an array element and see if it could possibly be out of bounds.

• Ensure that you are not declaring too much memory. 64 MB is guaranteed, but having an array of size [100000][100000] will never work.

• Ensure that you are not declaring too much stack memory. Any large arrays should be declared globally, outside of any functions - putting an array of 100000 ints/integers inside a function probably will not work.

 

21. Where do we get our certificate? Do we get participation certificates?

The certificate of the top 20 winners of Hackathon and the top 140 winners of Code Battle is sent to their respective schools after due verifications. All participants receive an e-participation certificate in their email within a week of the competition concluding.