search

Earn with igits

Jan 12, 2025 pm 06:12 PM

Earn with igits

Weekly Challenge 303: Python and Perl Solutions

Mohammad S. Anwar's Weekly Challenge provides a regular coding exercise. My solutions, presented below, are initially crafted in Python and then adapted to Perl. This dual approach enhances coding proficiency.

Challenge 303: Solutions

Task 1: Generating Even 3-Digit Integers

Task Description:

Given a list of positive integers, generate all unique even 3-digit integers that can be formed using the digits from the list.

Python Solution:

This Python solution leverages the itertools.permutations function to efficiently generate all possible 3-digit combinations. A set is used to maintain uniqueness.

from itertools import permutations

def three_digits_even(ints: list) -> list:
    solution = set()
    for p in permutations(ints, 3):
        num_str = "".join(map(str, p))
        num = int(num_str)
        if num >= 100 and num % 2 == 0 and num_str[0] != '0':
            solution.add(num)
    return sorted(list(solution))

Perl Solution:

The Perl equivalent uses the Algorithm::Permute module for permutations and a hash to ensure uniqueness.

use Algorithm::Permute;
sub three_digits_even {
    my @ints = @_;
    my %seen;
    my @result;
    my $p = Algorithm::Permute->new(\@ints, 3);
    while (my @perm = $p->next) {
        my $num_str = join('', @perm);
        my $num = $num_str;
        if ($num >= 100 and $num % 2 == 0 and $num_str !~ /^0/) {
            push @result, $num unless $seen{$num}++;
        }
    }
    return sort {$a <=> $b} @result;
}

Examples:

<code># Python
print(three_digits_even([2, 1, 3, 0]))  # Output: [102, 120, 130, 132, 210, 230, 302, 310, 312, 320]
print(three_digits_even([2, 2, 8, 8, 2])) # Output: [222, 228, 282, 288, 822, 828, 882]

# Perl
print "@{[three_digits_even(2, 1, 3, 0)]}\n"; # Output: 102 120 130 132 210 230 302 310 312 320
print "@{[three_digits_even(2, 2, 8, 8, 2)]}\n"; # Output: 222 228 282 288 822 828 882</code>

Task 2: Delete and Earn

Task Description:

Given an array of integers, find the maximum number of points you can earn by repeatedly deleting an element, earning its value, and then deleting all elements with values one less and one more than the deleted element.

Python Solution:

This Python solution uses a Counter to track element frequencies and employs a recursive function to explore different deletion strategies.

from collections import Counter

def delete_and_earn(ints: list) -> int:
    freq = Counter(ints)
    return max_score(freq)

def max_score(freq: Counter) -> int:
    max_points = 0
    for num in list(freq): # Iterate through a copy to safely delete
        points = num * freq[num]
        new_freq = freq.copy()
        del new_freq[num]
        if num - 1 in new_freq:
            del new_freq[num - 1]
        if num + 1 in new_freq:
            del new_freq[num + 1]
        max_points = max(max_points, points + (0 if not new_freq else max_score(new_freq)))
    return max_points

Perl Solution:

The Perl solution mirrors the Python approach using a hash for frequency counting and a recursive function.

sub delete_and_earn {
    my %freq = map { $_ => 1 + $freq{$_} // 0 } @_;
    return max_score(\%freq);
}

sub max_score {
    my $freq = shift;
    my $max_points = 0;
    foreach my $num (keys %$freq) {
        my $points = $num * $freq->{$num};
        my %new_freq = %$freq;
        delete $new_freq{$num};
        delete $new_freq{$num - 1};
        delete $new_freq{$num + 1};
        $max_points = max($max_points, $points + (0 || max_score(\%new_freq)));
    }
    return $max_points;
}

sub max {
    return shift if @_ == 1;
    return $_[0] > $_[1] ? $_[0] : $_[1];
}

Examples:

<code># Python
print(delete_and_earn([3, 4, 2]))  # Output: 6
print(delete_and_earn([2, 2, 3, 3, 3, 4])) # Output: 9

# Perl
print delete_and_earn(3, 4, 2), "\n";  # Output: 6
print delete_and_earn(2, 2, 3, 3, 3, 4), "\n"; # Output: 9</code>

These solutions demonstrate efficient and clear approaches to solving both tasks in the Weekly Challenge 303. The use of both Python and Perl highlights the transferable nature of algorithmic problem-solving across different programming languages.

The above is the detailed content of Earn with igits. For more information, please follow other related articles on the PHP Chinese website!

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Learning Python: Is 2 Hours of Daily Study Sufficient?Learning Python: Is 2 Hours of Daily Study Sufficient?Apr 18, 2025 am 12:22 AM

Is it enough to learn Python for two hours a day? It depends on your goals and learning methods. 1) Develop a clear learning plan, 2) Select appropriate learning resources and methods, 3) Practice and review and consolidate hands-on practice and review and consolidate, and you can gradually master the basic knowledge and advanced functions of Python during this period.

Python for Web Development: Key ApplicationsPython for Web Development: Key ApplicationsApr 18, 2025 am 12:20 AM

Key applications of Python in web development include the use of Django and Flask frameworks, API development, data analysis and visualization, machine learning and AI, and performance optimization. 1. Django and Flask framework: Django is suitable for rapid development of complex applications, and Flask is suitable for small or highly customized projects. 2. API development: Use Flask or DjangoRESTFramework to build RESTfulAPI. 3. Data analysis and visualization: Use Python to process data and display it through the web interface. 4. Machine Learning and AI: Python is used to build intelligent web applications. 5. Performance optimization: optimized through asynchronous programming, caching and code

Python vs. C  : Exploring Performance and EfficiencyPython vs. C : Exploring Performance and EfficiencyApr 18, 2025 am 12:20 AM

Python is better than C in development efficiency, but C is higher in execution performance. 1. Python's concise syntax and rich libraries improve development efficiency. 2.C's compilation-type characteristics and hardware control improve execution performance. When making a choice, you need to weigh the development speed and execution efficiency based on project needs.

Python in Action: Real-World ExamplesPython in Action: Real-World ExamplesApr 18, 2025 am 12:18 AM

Python's real-world applications include data analytics, web development, artificial intelligence and automation. 1) In data analysis, Python uses Pandas and Matplotlib to process and visualize data. 2) In web development, Django and Flask frameworks simplify the creation of web applications. 3) In the field of artificial intelligence, TensorFlow and PyTorch are used to build and train models. 4) In terms of automation, Python scripts can be used for tasks such as copying files.

Python's Main Uses: A Comprehensive OverviewPython's Main Uses: A Comprehensive OverviewApr 18, 2025 am 12:18 AM

Python is widely used in data science, web development and automation scripting fields. 1) In data science, Python simplifies data processing and analysis through libraries such as NumPy and Pandas. 2) In web development, the Django and Flask frameworks enable developers to quickly build applications. 3) In automated scripts, Python's simplicity and standard library make it ideal.

The Main Purpose of Python: Flexibility and Ease of UseThe Main Purpose of Python: Flexibility and Ease of UseApr 17, 2025 am 12:14 AM

Python's flexibility is reflected in multi-paradigm support and dynamic type systems, while ease of use comes from a simple syntax and rich standard library. 1. Flexibility: Supports object-oriented, functional and procedural programming, and dynamic type systems improve development efficiency. 2. Ease of use: The grammar is close to natural language, the standard library covers a wide range of functions, and simplifies the development process.

Python: The Power of Versatile ProgrammingPython: The Power of Versatile ProgrammingApr 17, 2025 am 12:09 AM

Python is highly favored for its simplicity and power, suitable for all needs from beginners to advanced developers. Its versatility is reflected in: 1) Easy to learn and use, simple syntax; 2) Rich libraries and frameworks, such as NumPy, Pandas, etc.; 3) Cross-platform support, which can be run on a variety of operating systems; 4) Suitable for scripting and automation tasks to improve work efficiency.

Learning Python in 2 Hours a Day: A Practical GuideLearning Python in 2 Hours a Day: A Practical GuideApr 17, 2025 am 12:05 AM

Yes, learn Python in two hours a day. 1. Develop a reasonable study plan, 2. Select the right learning resources, 3. Consolidate the knowledge learned through practice. These steps can help you master Python in a short time.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
1 months agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Best Graphic Settings
1 months agoBy尊渡假赌尊渡假赌尊渡假赌
Will R.E.P.O. Have Crossplay?
1 months agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

PhpStorm Mac version

PhpStorm Mac version

The latest (2018.2.1) professional PHP integrated development tool

SublimeText3 Linux new version

SublimeText3 Linux new version

SublimeText3 Linux latest version

VSCode Windows 64-bit Download

VSCode Windows 64-bit Download

A free and powerful IDE editor launched by Microsoft

ZendStudio 13.5.1 Mac

ZendStudio 13.5.1 Mac

Powerful PHP integrated development environment

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor