Contest Experiences | AtCoder Beginner Contest 322

With the increase in demand for coding in the tech industry people started solving coding questions on different platforms, one of the platforms that provide opportunities for coders to practice their skills is AtCoder. On their platform, different types of contests are available such as AHC (AtCoder Heuristic Contest), AGC (AtCoder Grand Contest), ARC (AtCoder Regular Contest), and ABC(AtCoder Beginner Contest).

About the Contest:

• Contest Date: 30/Sept/2023.
• Contest Time: 05:30 pm (IST)
• Duration: 100 minutes
• Number of Questions: 7
• Question-wise point values: 100-200-250-400-475-550-600
• Contest Rule: you get a score assigned to it.
• Rank Computed: From the total marks of Question- [(the time you spend to get your current score) + (5 minutes) * (the number of incorrect attempts)].

Link of Contest: https://atcoder.jp/contests/abc322/tasks

Overview of the Challenge:

Problem Name	Difficulty	Pre-Requisite	Approx. Time to Solve
First ABC 2	Easy	Contiguous Substring	5-7 min
Prefix and Suffix	Easy	String Matching	5-7 min
Festival	Easy	Loops	10 min
Polyomino	Medium	backtracking algorithm	10 min
Product Development	Medium	Dynamic Programming	10-15 min
Vacation Query	Medium	String Sequence	10 min
Two Kinds of Base	Medium	modulo 998244353	15 min

Problem 1: First ABC 2

This question is pretty straightforward if you know about substring. You need to find the first occurrence of ‘ABC’ in a given string.

Problem 2: Prefix and Suffix

In this question, two strings are given you need to return Prefix if the first ‘N’ character of the second string coincides with the first string and Suffix if the last ‘N’ character of the second string coincides with the first string.

Problem 3: Festival

In this question the festival will be celebrated for ‘N’ Days and Fireworks will be held for ‘M’ days. Given, fireworks will be done on the last day. You need to find out how many days later the firework will happen from a given day.

Problem 4: Polyomino

In a given 4×4 grid, you need to fit 3 polynomials such that those polynomials do not overlap with each other and the grid is entirely covered. You need to have a good knowledge of Backtracking for this question.

Problem 5: Product Development

In this problem, you need to raise the parameter of a product to a certain value. To achieve this there are different development plans, you need to check which development plan costs the minimum to achieve the goal.

Problem 6: Vacation Query

In this problem, Given a string that contains only ‘0’ and ‘1’, and based on different parameters you need to either print the number of ‘1’ in each sequence of string. or you need to change the number of ‘0’ and ‘1’ in the given string.

Problem 7: Two Kinds of Base

You need to count the number of nonnegative triplets that follow the given condition. After getting the number of triplets you need to modulo with 998244353.

Conclusion:

• A mix of straightforward and challenging questions
• Substring search, string manipulation, and backtracking required for some problems
• Covers various topics and problem-solving techniques
• Suitable for those looking to improve their competitive programming skills
• Recommended for those familiar with substring searching and string manipulation
• Great platform for mastering competitive programming