{"id":23154448,"url":"https://github.com/mericluc/ecv-queens","last_synced_at":"2026-06-14T21:32:44.886Z","repository":{"id":63053198,"uuid":"564418769","full_name":"MericLuc/ecv-queens","owner":"MericLuc","description":"ECV Application : N Queens","archived":false,"fork":false,"pushed_at":"2022-11-12T19:58:22.000Z","size":1346,"stargazers_count":0,"open_issues_count":0,"forks_count":0,"subscribers_count":1,"default_branch":"dev","last_synced_at":"2025-08-08T16:37:37.436Z","etag":null,"topics":["cpp","cpp17","dlx-algorithm","n-queens","qt","qt5"],"latest_commit_sha":null,"homepage":"","language":"C++","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":null,"status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/MericLuc.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":null,"code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null}},"created_at":"2022-11-10T17:15:29.000Z","updated_at":"2022-11-10T17:19:19.000Z","dependencies_parsed_at":"2022-11-11T22:02:20.066Z","dependency_job_id":null,"html_url":"https://github.com/MericLuc/ecv-queens","commit_stats":null,"previous_names":[],"tags_count":0,"template":false,"template_full_name":null,"purl":"pkg:github/MericLuc/ecv-queens","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/MericLuc%2Fecv-queens","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/MericLuc%2Fecv-queens/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/MericLuc%2Fecv-queens/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/MericLuc%2Fecv-queens/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/MericLuc","download_url":"https://codeload.github.com/MericLuc/ecv-queens/tar.gz/refs/heads/dev","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/MericLuc%2Fecv-queens/sbom","scorecard":null,"host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":286080680,"owners_count":34339194,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2026-05-26T15:22:16.424Z","status":"online","status_checked_at":"2026-06-14T02:00:07.365Z","response_time":62,"last_error":null,"robots_txt_status":"success","robots_txt_updated_at":"2025-07-24T06:49:26.215Z","robots_txt_url":"https://github.com/robots.txt","online":true,"can_crawl_api":true,"host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["cpp","cpp17","dlx-algorithm","n-queens","qt","qt5"],"created_at":"2024-12-17T20:12:49.123Z","updated_at":"2026-06-14T21:32:44.865Z","avatar_url":"https://github.com/MericLuc.png","language":"C++","funding_links":[],"categories":[],"sub_categories":[],"readme":"# ECV - Sudoku\n\n**:star2: Exact cover problem - N Queens application :star2:**\n\nGraphic toy written in C++/Qt to solve the [**N Queens problem**](https://en.wikipedia.org/wiki/Eight_queens_puzzle).\n\nUnder the hood, it uses the [**ECV library**](https://github.com/MericLuc/ecv) that implements [Donald Knuth's Algorithm X](https://arxiv.org/pdf/cs/0011047v1.pdf). \n\n![example](imgs/example.gif)\n\n## How to build/install\n\n_Dependencies_ : \n  - Qt5 (Qt5::Widgets Qt5::Svg packages)\n  - ecv (as a submodule)\n\nStart by getting the sources :\n\n```\n[~/git] git clone https://github.com/MericLuc/ecv-queens.git\n[~/git] git submodule update --init --recursive\n```\n\nThen, the easiest way to build is to use it as a QtCreator project.\n\nOtherwise, you can build from command-line using cmake and defining a bunch of Qt related variables.\n\nIt should be something like that (not garanteed) : \n\n```\n[~/builds] cmake -S ${PATH_TO_PROJECT} -B ${PATH_TO_BUILD} -DCMAKE_BUILD_TYPE=Release -DCMAKE_PREFIX_PATH=${PATH_TO_QT_INSTALL}\n[~/builds] make\n```\n\n## Example usage\n\n[**Play**](https://mericluc.github.io/ecv/queens/app.html) in your browser using a [webassembly](https://webassembly.org/) compiled version.\n\n_Rules_ : \n  - Hover a cell to select it.\n  - Left-click to add/remove a queen to a cell.\n  - For the rest, I think the UI buttons are self-explanatory 😁\n\n## Acknowledgements\n\n[This article](https://www.nohuddleoffense.de/2019/01/20/dancing-links-algorithm-x-and-the-n-queens-puzzle/) was pretty useful, especially to realize the concept of \"primary/secondary\" constraints in exact-cover problems.","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fmericluc%2Fecv-queens","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fmericluc%2Fecv-queens","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fmericluc%2Fecv-queens/lists"}