{"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":1219,"title":"Mystery problem","description":"Given integer x between 1 and 50, return integer y=mystery(x), where \r\n\r\n   mystery(1) =  111   mystery(6)  =  809  ...  mystery(46) = 1809\r\n   mystery(2) =  301   mystery(7)  = 2120  ...  mystery(47) = 1319\r\n   mystery(3) =  315   mystery(8)  = 1413  ...  mystery(48) = 1201\r\n   mystery(4) = 2301   mystery(9)  = 1422  ...  mystery(49) =  405\r\n   mystery(5) = 2325   mystery(10) = 1320  ...  mystery(50) =  612 \r\n\r\nThe rest are for you to determine. Your function should allow a row vector as input and produce a row vector as a result, e.g.,\r\n\r\n   mystery(1:3)=[111 301 315].\r\n\r\nHint: this is not really a mathematical problem--the answer will be just a lookup table.","description_html":"\u003cp\u003eGiven integer x between 1 and 50, return integer y=mystery(x), where\u003c/p\u003e\u003cpre\u003e   mystery(1) =  111   mystery(6)  =  809  ...  mystery(46) = 1809\r\n   mystery(2) =  301   mystery(7)  = 2120  ...  mystery(47) = 1319\r\n   mystery(3) =  315   mystery(8)  = 1413  ...  mystery(48) = 1201\r\n   mystery(4) = 2301   mystery(9)  = 1422  ...  mystery(49) =  405\r\n   mystery(5) = 2325   mystery(10) = 1320  ...  mystery(50) =  612 \u003c/pre\u003e\u003cp\u003eThe rest are for you to determine. Your function should allow a row vector as input and produce a row vector as a result, e.g.,\u003c/p\u003e\u003cpre\u003e   mystery(1:3)=[111 301 315].\u003c/pre\u003e\u003cp\u003eHint: this is not really a mathematical problem--the answer will be just a lookup table.\u003c/p\u003e","function_template":"function y=mystery(x)\r\ny=0;\r\n","test_suite":"%%\r\nassert(isequal(mystery(1:5),[111 301 315 2301 2325]))\r\n%%\r\nassert(isequal(mystery(6:10),[809 2120 1413 1422 1320]))\r\n%%\r\nassert(isequal(mystery(46:50),[1809 1319 1201 405 612]))\r\n%%\r\nx=1:50;\r\nm=mystery(x);\r\nassert(all(m==round(m)))\r\ny=spline(x,m,[12.5 37.5]);\r\nassert(all(y==[704.84846527373202 1283.5708406360138]))","published":true,"deleted":false,"likes_count":3,"comments_count":12,"created_by":245,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":15,"test_suite_updated_at":"2013-01-28T15:31:56.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2013-01-22T15:48:02.000Z","updated_at":"2026-05-26T16:50:04.000Z","published_at":"2013-01-22T15:51:00.000Z","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\u003eGiven integer x between 1 and 50, return integer y=mystery(x), where\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[   mystery(1) =  111   mystery(6)  =  809  ...  mystery(46) = 1809\\n   mystery(2) =  301   mystery(7)  = 2120  ...  mystery(47) = 1319\\n   mystery(3) =  315   mystery(8)  = 1413  ...  mystery(48) = 1201\\n   mystery(4) = 2301   mystery(9)  = 1422  ...  mystery(49) =  405\\n   mystery(5) = 2325   mystery(10) = 1320  ...  mystery(50) =  612]]\u003e\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\u003eThe rest are for you to determine. Your function should allow a row vector as input and produce a row vector as a result, e.g.,\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[   mystery(1:3)=[111 301 315].]]\u003e\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\u003eHint: this is not really a mathematical problem--the answer will be just a lookup table.\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":1219,"title":"Mystery problem","description":"Given integer x between 1 and 50, return integer y=mystery(x), where \r\n\r\n   mystery(1) =  111   mystery(6)  =  809  ...  mystery(46) = 1809\r\n   mystery(2) =  301   mystery(7)  = 2120  ...  mystery(47) = 1319\r\n   mystery(3) =  315   mystery(8)  = 1413  ...  mystery(48) = 1201\r\n   mystery(4) = 2301   mystery(9)  = 1422  ...  mystery(49) =  405\r\n   mystery(5) = 2325   mystery(10) = 1320  ...  mystery(50) =  612 \r\n\r\nThe rest are for you to determine. Your function should allow a row vector as input and produce a row vector as a result, e.g.,\r\n\r\n   mystery(1:3)=[111 301 315].\r\n\r\nHint: this is not really a mathematical problem--the answer will be just a lookup table.","description_html":"\u003cp\u003eGiven integer x between 1 and 50, return integer y=mystery(x), where\u003c/p\u003e\u003cpre\u003e   mystery(1) =  111   mystery(6)  =  809  ...  mystery(46) = 1809\r\n   mystery(2) =  301   mystery(7)  = 2120  ...  mystery(47) = 1319\r\n   mystery(3) =  315   mystery(8)  = 1413  ...  mystery(48) = 1201\r\n   mystery(4) = 2301   mystery(9)  = 1422  ...  mystery(49) =  405\r\n   mystery(5) = 2325   mystery(10) = 1320  ...  mystery(50) =  612 \u003c/pre\u003e\u003cp\u003eThe rest are for you to determine. Your function should allow a row vector as input and produce a row vector as a result, e.g.,\u003c/p\u003e\u003cpre\u003e   mystery(1:3)=[111 301 315].\u003c/pre\u003e\u003cp\u003eHint: this is not really a mathematical problem--the answer will be just a lookup table.\u003c/p\u003e","function_template":"function y=mystery(x)\r\ny=0;\r\n","test_suite":"%%\r\nassert(isequal(mystery(1:5),[111 301 315 2301 2325]))\r\n%%\r\nassert(isequal(mystery(6:10),[809 2120 1413 1422 1320]))\r\n%%\r\nassert(isequal(mystery(46:50),[1809 1319 1201 405 612]))\r\n%%\r\nx=1:50;\r\nm=mystery(x);\r\nassert(all(m==round(m)))\r\ny=spline(x,m,[12.5 37.5]);\r\nassert(all(y==[704.84846527373202 1283.5708406360138]))","published":true,"deleted":false,"likes_count":3,"comments_count":12,"created_by":245,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":15,"test_suite_updated_at":"2013-01-28T15:31:56.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2013-01-22T15:48:02.000Z","updated_at":"2026-05-26T16:50:04.000Z","published_at":"2013-01-22T15:51:00.000Z","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\u003eGiven integer x between 1 and 50, return integer y=mystery(x), where\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[   mystery(1) =  111   mystery(6)  =  809  ...  mystery(46) = 1809\\n   mystery(2) =  301   mystery(7)  = 2120  ...  mystery(47) = 1319\\n   mystery(3) =  315   mystery(8)  = 1413  ...  mystery(48) = 1201\\n   mystery(4) = 2301   mystery(9)  = 1422  ...  mystery(49) =  405\\n   mystery(5) = 2325   mystery(10) = 1320  ...  mystery(50) =  612]]\u003e\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\u003eThe rest are for you to determine. Your function should allow a row vector as input and produce a row vector as a result, e.g.,\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[   mystery(1:3)=[111 301 315].]]\u003e\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\u003eHint: this is not really a mathematical problem--the answer will be just a lookup table.\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":"medium","count":1,"selected":false}]],"term":"tag:\"ISO 3166-2\"","page":1,"per_page":50,"sort":"map(difficulty_value,0,0,999) asc"}}