{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2026-05-26T00:16:20.000Z","description":"Problems submitted by members of the MATLAB Central community.","is_default":true,"created_by":161519,"badge_id":null,"featured":false,"trending":false,"solution_count_in_trending_period":0,"trending_last_calculated":"2026-05-26T00:00:00.000Z","image_id":null,"published":true,"community_created":false,"status_id":2,"is_default_group_for_player":false,"deleted_by":null,"deleted_at":null,"restored_by":null,"restored_at":null,"description_opc":null,"description_html":null,"published_at":null},"problems":[{"id":3690,"title":"OXO counting","description":"Count the number of occurrences of \"OXO\" in rows, columns, diagonals and anti-diagonals.\r\n\r\n\r\nExample:\r\n\r\n    \u003e\u003e board = ['OOX'\r\n                'XXO'\r\n                'OXO'];\r\n    \u003e\u003e count_OXO(board)\r\n    ans =\r\n       3\r\n    \u003e\u003e board = [' O '\r\n                'XXO'\r\n                'OXO'];\r\n    \u003e\u003e count_OXO(board)\r\n    ans =\r\n       1","description_html":"\u003cp\u003eCount the number of occurrences of \"OXO\" in rows, columns, diagonals and anti-diagonals.\u003c/p\u003e\u003cp\u003eExample:\u003c/p\u003e\u003cpre\u003e    \u0026gt;\u0026gt; board = ['OOX'\r\n                'XXO'\r\n                'OXO'];\r\n    \u0026gt;\u0026gt; count_OXO(board)\r\n    ans =\r\n       3\r\n    \u0026gt;\u0026gt; board = [' O '\r\n                'XXO'\r\n                'OXO'];\r\n    \u0026gt;\u0026gt; count_OXO(board)\r\n    ans =\r\n       1\u003c/pre\u003e","function_template":"function y = count_OXO(board)\r\n  y = ;\r\nend","test_suite":"%%\r\nboard = 'OXO';\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = '';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = '   ';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ' X ';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'O O';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'O O OXO X';\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OOX';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OOXOX';\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OOX OX';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OOXXO';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OOXOOOOXXOXOX';\r\ny_correct = 2;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OOO';'OXO';'OXO'];\r\ny_correct = 4;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OOO';'OXO';'OOO'];\r\ny_correct = 4;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OXX';'XXX';'XOO'];\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OOO';'X O';'OXO'];\r\ny_correct = 2;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['     ';'     ';'     ';'     '];\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['O OO';'O XO';'OOX '];\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OXXOXO';' OXO X';'XOXOXO'];\r\ny_correct = 6;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OXOXOXO';'OXOXO X';'XOOOXOX'];\r\ny_correct = 8;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OXO'.';\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\n% Keep in mind that Test Suite may be extended, so try to write general solution.\r\n% If you find any bugs, please report it to me. Thanks!\r\n% Have fun.","published":true,"deleted":false,"likes_count":3,"comments_count":0,"created_by":14358,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":19,"test_suite_updated_at":"2017-08-31T12:44:18.000Z","rescore_all_solutions":true,"group_id":1,"created_at":"2015-03-24T21:25:19.000Z","updated_at":"2026-05-24T17:21:11.000Z","published_at":"2017-08-31T09:25:21.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eCount the number of occurrences of \\\"OXO\\\" in rows, columns, diagonals and anti-diagonals.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eExample:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"code\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e\u003c![CDATA[    \u003e\u003e board = ['OOX'\\n                'XXO'\\n                'OXO'];\\n    \u003e\u003e count_OXO(board)\\n    ans =\\n       3\\n    \u003e\u003e board = [' O '\\n                'XXO'\\n                'OXO'];\\n    \u003e\u003e count_OXO(board)\\n    ans =\\n       1]]\u003e\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"}]}"}],"problem_search":{"problems":[{"id":3690,"title":"OXO counting","description":"Count the number of occurrences of \"OXO\" in rows, columns, diagonals and anti-diagonals.\r\n\r\n\r\nExample:\r\n\r\n    \u003e\u003e board = ['OOX'\r\n                'XXO'\r\n                'OXO'];\r\n    \u003e\u003e count_OXO(board)\r\n    ans =\r\n       3\r\n    \u003e\u003e board = [' O '\r\n                'XXO'\r\n                'OXO'];\r\n    \u003e\u003e count_OXO(board)\r\n    ans =\r\n       1","description_html":"\u003cp\u003eCount the number of occurrences of \"OXO\" in rows, columns, diagonals and anti-diagonals.\u003c/p\u003e\u003cp\u003eExample:\u003c/p\u003e\u003cpre\u003e    \u0026gt;\u0026gt; board = ['OOX'\r\n                'XXO'\r\n                'OXO'];\r\n    \u0026gt;\u0026gt; count_OXO(board)\r\n    ans =\r\n       3\r\n    \u0026gt;\u0026gt; board = [' O '\r\n                'XXO'\r\n                'OXO'];\r\n    \u0026gt;\u0026gt; count_OXO(board)\r\n    ans =\r\n       1\u003c/pre\u003e","function_template":"function y = count_OXO(board)\r\n  y = ;\r\nend","test_suite":"%%\r\nboard = 'OXO';\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = '';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = '   ';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ' X ';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'O O';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'O O OXO X';\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OOX';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OOXOX';\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OOX OX';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OOXXO';\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OOXOOOOXXOXOX';\r\ny_correct = 2;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OOO';'OXO';'OXO'];\r\ny_correct = 4;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OOO';'OXO';'OOO'];\r\ny_correct = 4;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OXX';'XXX';'XOO'];\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OOO';'X O';'OXO'];\r\ny_correct = 2;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['     ';'     ';'     ';'     '];\r\ny_correct = 0;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['O OO';'O XO';'OOX '];\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OXXOXO';' OXO X';'XOXOXO'];\r\ny_correct = 6;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = ['OXOXOXO';'OXOXO X';'XOOOXOX'];\r\ny_correct = 8;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\nboard = 'OXO'.';\r\ny_correct = 1;\r\nassert(isequal(count_OXO(board),y_correct))\r\n%%\r\n% Keep in mind that Test Suite may be extended, so try to write general solution.\r\n% If you find any bugs, please report it to me. Thanks!\r\n% Have fun.","published":true,"deleted":false,"likes_count":3,"comments_count":0,"created_by":14358,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":19,"test_suite_updated_at":"2017-08-31T12:44:18.000Z","rescore_all_solutions":true,"group_id":1,"created_at":"2015-03-24T21:25:19.000Z","updated_at":"2026-05-24T17:21:11.000Z","published_at":"2017-08-31T09:25:21.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eCount the number of occurrences of \\\"OXO\\\" in rows, columns, diagonals and anti-diagonals.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eExample:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"code\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e\u003c![CDATA[    \u003e\u003e board = ['OOX'\\n                'XXO'\\n                'OXO'];\\n    \u003e\u003e count_OXO(board)\\n    ans =\\n       3\\n    \u003e\u003e board = [' O '\\n                'XXO'\\n                'OXO'];\\n    \u003e\u003e count_OXO(board)\\n    ans =\\n       1]]\u003e\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"}]}"}],"errors":[],"facets":[[{"value":"Paper-\u0026-pencil Games","count":1,"selected":false}],[{"value":"medium","count":1,"selected":false}]],"term":"tag:\"pattern analysis\"","page":1,"per_page":50,"sort":"map(difficulty_value,0,0,999) asc"}}