USACO (USA Computing Olympiad)

Overview:

A highly respected online programming competition for middle and high school students worldwide. It is the U.S. national pathway to the IOI.

Divisions:

• Bronze – beginner level

• Silver – intermediate

• Gold – advanced

• Platinum – elite (pre-IOI level)

Language Support:

C++, Java, Python (limited for upper divisions).

Schedule:

Four contests per year (Dec, Jan, Feb, March).

Highlights:

• Fully online and auto-graded.

• Great for self-paced learning and progression.

• Strong emphasis on problem-solving and algorithmic thinking.

LeetCode (Online Coding Platform)

Overview:

A global online coding platform widely used for technical interview preparation, algorithm practice, and coding competitions.

Problem Types:

Covers arrays, strings, trees, graphs, dynamic programming, and much more.

Contests:

• Weekly Contests

• Biweekly Contests

• LeetCode Cup (China region)

Language Support:

Python, C++, Java, JavaScript, Go, and more.

Highlights:

• Problems range from easy to hard.

• Useful for both competition prep and real-world job interviews.

• Community solutions and discussions available for learning.

NOI (National Olympiad in Informatics, China)

Overview:

The most prestigious informatics competition for high school students in China. It serves as the path to the IOI (International Olympiad in Informatics) through national team selection.

Structure:

• CSP, NOIP, then NOI

• National team members are selected from NOI training camps

Language:

Primarily C++, with emphasis on efficiency and algorithm depth.

Highlights:

• Extremely competitive.

• Mastery of algorithms like DP, graphs, trees, search, and optimization is required.

• Medals are highly valued for university admissions in China.

CCC (Canadian Computing Competition)

Overview:

Organized by the University of Waterloo, CCC is a prestigious algorithmic programming competition for high school students, open to both Canadian and international participants.

Levels:

• Junior: Focuses on logic, simple programming tasks.

• Senior: Focuses on data structures, algorithmic problem solving.

Language Support:

Python, C++, Java.

Timing:

Held annually in February.

Highlights:

• Recognized by top universities in Canada and abroad.

• Top scorers are invited to CCO (Canadian Computing Olympiad), a stepping stone to the IOI.

• Problems emphasize clarity, logic, and clean algorithmic thinking.

Preparing for the USA Computing Olympiad (USACO) requires a structured learning schedule, determination, and practice. Here's a step-by-step guide to help you build an effective learning plan:

1. **Understand the Basics:**

   - Familiarize yourself with the rules, format, and difficulty levels of USACO contests.

   - Explore past contest problems and their solutions on the USACO website.

2. **Choose a Programming Language:**

   - Select a language you're comfortable with for competitive programming. Common choices include C++, Python, and Java.

3. **Learn Data Structures and Algorithms:**

   - Develop a strong foundation in data structures (arrays, lists, stacks, queues, trees, graphs) and algorithms (sorting, searching, dynamic programming, etc.).

   - Study books like "Introduction to Algorithms" by Cormen, Leiserson, Rivest, and Stein, and take online courses or tutorials on data structures and algorithms.

4. **Practice Contest Problems:**

   - Start with the USACO Training Gateway, which offers a variety of problems and solutions.

   - Use online judges like Codeforces, AtCoder, and LeetCode to practice similar problems.

5. **Participate in Contests:**

   - Join local programming contests or online contests regularly to build your problem-solving skills under time pressure.

   - Use platforms like Codeforces, TopCoder, and CodeChef to compete in contests.

6. **Read and Analyze Solutions:**

   - After solving problems or participating in contests, study the solutions of others, especially those with higher ratings.

   - Understand different approaches, algorithms, and coding styles.

7. **Review and Refine Your Code:**

   - Maintain a personal library of algorithms and code snippets for quick reference during contests.

   - Keep your code clean, efficient, and well-documented.

8. **Simulate Contest Conditions:**

   - Practice by simulating real USACO contest conditions—use the same environment and time constraints.

   - Refrain from using external help during practice contests.

9. **Participate in Mock Contests:**

   - Join online platforms that offer mock USACO contests. These contests mimic the official USACO experience.

10. **Master USACO-Specific Topics:**

    - USACO often features topics like depth-first search (DFS), breadth-first search (BFS), dynamic programming, greedy algorithms, and more. Focus on mastering these.

11. **Read and Review Problems:**

    - Carefully read the contest problems and understand their requirements before starting to code.

    - Test your code thoroughly on sample inputs and edge cases.

12. **Time Management:**

    - Allocate time for learning, practice, and taking breaks. Regular, consistent practice is more effective than occasional cramming.

13. **Seek Help and Collaborate:**

    - Join online forums or communities where you can ask questions and discuss problems.

    - Collaborate with other competitive programmers to learn and grow together.

14. **Stay Updated:**

    - Keep an eye on the USACO website and mailing list for announcements about contests, dates, and rule changes.

15. **Stay Persistent:**

    - Competitive programming can be challenging, but persistence is key. Don't get discouraged by initial failures; keep practicing and learning from your mistakes.

Remember that consistent practice, a solid understanding of algorithms and data structures, and the ability to think critically and creatively are the keys to success in USACO. Good luck with your preparations!

BEIJING (Reuters) - China's aviation industry sank further into the red, losing 34.25 billion yuan ($4.89 billion) in the second quarter, only slightly narrower than in the first quarter, underlining the colossal financial impact from the coronavirus pandemic.

In the first quarter the industry, which includes airlines, airports and other aviation companies, lost 38.1 billion yuan, according to data released by the Civil Aviation Administration of China (CAAC) on Friday.

China's aviation industry has been recovering faster than most countries emerging from the COVID lockdowns, underpinned by a steady recovery in the domestic travel market after the epidemic was largely brought under control.

But passenger numbers showed the sector is still way below pre-COVID-19 levels, according to the latest official data. June passenger numbers fell 42.4% from a year earlier to 30.74 million, the CAAC said, although that was better than a 52.6% decline in May.

In the first half this year, total passenger numbers dropped by 45.8% from a year ago.

To boost cashflows, a few Chinese airlines have recently rolled out discount passes that would allow passengers unlimited domestic travel with few restrictions. China Eastern Airlines (SS:600115) is the first in June to sell "fly at will" flight passes for unlimited weekend domestic travel until the end of the year.

The deal was met with great consumer enthusiasm and more airlines followed suit. Hainan Airlines (SS:600221) this month offered consumers flight passes that would enable them to make unlimited trips to or from Hainan island, a popular tropical tourist spot.

TOKYO (Reuters) - International Monetary Fund Chief Economist Gita Gopinath said on Friday governments must shift to "equity-like" support from one focused on liquidity provision as the coronavirus pandemic inflicts prolonged harm on companies.

Government support in the form of loans would saddle companies with huge debt, which would serve like a tax that makes it difficult for them to emerge from the crisis, she said.

"If the lending takes form more like equity ... then that's less onus on the firms. That will make it easier for firms to recover from the crisis," Gopinath said in a webinar co-hosted by the IMF and the University of Tokyo.

TOKYO (Reuters) - Japan is likely to revise its economic assessment up slightly at its monthly report for July, government officials said, nodding to growing signs the economy is gradually emerging from the impact of the coronavirus pandemic.

The change in assessment, which would be the second straight month of upgrade, would reflect a rebound in service-sector sentiment and signs of recovery in exports to China, the officials told Reuters on condition of anonymity as they were not authorised to speak publicly.

In June, the government said that the economy was in a severe state but that it was showing signs of bottoming out.

By Nate Raymond

BOSTON (Reuters) - A federal appeals court on Thursday cleared the way for prosecutors to seek longer prison sentences for a founder and supervisory pharmacist of a Massachusetts compounding pharmacy whose tainted drugs sparked a deadly fungal meningitis outbreak in 2012.

The 1st U.S. Circuit Court of Appeals in Boston upheld the racketeering and fraud convictions of Barry Cadden, New England Compounding Center's ex-president, and Glenn Chin, its former supervisory pharmacist.

But the three-judge panel said a trial judge erred in sentencing Cadden, 53, and Chin, 52, to nine and eight years in prison, respectively, when he declined to apply various federal sentencing guideline enhancements.

U.S. Circuit Judge David Barron said the judge, among other things, in calculating a sentence wrongly concluded only the hospitals that bought NECC's drugs could count as victims and not the patients who used them.

But the court also ruled the judge did not wrongly undercalculate the victims' financial losses, which posed "the greatest risk of substantially increasing our client's sentence," said Bruce Singal, Cadden's lawyer.

Prosecutors had cited larger losses in seeking 35-year prison terms.

Both men were indicted in 2014 after a fungal meningitis outbreak traced back to mold-tainted steroids that prosecutors say NECC produced in filthy and unsafe conditions and shipped to hospitals and clinics nationally.

The outbreak sickened 793 patients, more than 100 of whom have died, prosecutors said.

Jurors in separate trials in 2017 acquitted Cadden and Chin of second-degree murder charges related to the deaths of 25 patients but convicted them of racketeering and fraud over alleged misrepresentations made to NECC's customers.

Prosecutors argued hospitals would not have bought drugs from Framingham, Massachusetts-based NECC had they known about its quality control issues.

Cadden and Chin also face separate second-degree murder charges in Michigan, which was hit hard by the outbreak.

WASHINGTON (Reuters) - President Donald Trump will sign three executive orders on lowering prescription drug prices, White House Chief of Staff Mark Meadows said on Thursday.

"This president is going to do three different executive orders that will substantially make sure that the average American gets to pay less for their prescription drugs," Meadows said in an interview on Fox Business Network.

Meadows did not give details and did not say when the executive orders would be signed.

On Monday, Meadows told Fox News the White House was looking to get something done on prescription drug prices after Congress failed to act.

Trump is trailing Democratic presidential candidate Joe Biden in opinion polls ahead of the Nov. 3 election and the cost of healthcare is a major issue in the campaign.

The Democratic-controlled House of Representatives on Monday passed a healthcare bill that includes provisions to cut prescription drug prices. The legislation is expected to be blocked in the Republican-controlled Senate.

By Dan Burns

(Reuters) - The U.S. Federal Reserve's holdings of bonds and other assets shrank for a fourth straight week, sliding below $7 trillion, and use of one key emergency liquidity measure dropped to zero in the latest sign that financial stresses that erupted early in the coronavirus pandemic have eased.

The Fed's total balance sheet size declined by about $88 billion to $6.97 trillion as of July 8 versus $7.06 trillion a week earlier, data released on Thursday by the central bank showed.

It was the largest weekly drop in more than 11 years, and the main driver was the balance of outstanding repurchase agreements - or repos - which fell to zero from $61.2 billion a week earlier. It was the first time in 10 months that banks have not tapped the Fed for this key source of short-term funding.

"In a sense, it is the end of an era," Jefferies (NYSE:JEF) economists Thomas Simons and Aneta Markowska wrote in a research note emailed Thursday afternoon.

The Fed began intervening in the repo market in mid-September after a shortfall of bank reserves led to a record surge in short-term borrowing costs. It ramped up that support to unprecedented levels in March after concerns over the rapidly spreading coronavirus disrupted financial markets.

Take-up of the Fed's repo operations waned over the past few months as markets stabilized and the Fed provided more liquidity through massive purchases of Treasury securities and mortgage-backed securities.

The central bank also tweaked the repo operations in June to make them slightly more expensive, positioning them as more of a backstop. That appears to be pushing banks to find private counterparties for their repo needs.

As evidence, there were no bids for a fourth straight day at Thursday's overnight repo offering from the Fed. Officials have pledged to keep monitoring financial conditions and offer more support if needed.

"They want to be seen as supplying more than enough to the system and they're going to err on the side of doing that," said Kathy Bostjancic, chief U.S. financial economist for Oxford Economics.