{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2025-12-14T01:33:56.000Z","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":"2025-12-14T00:00:00.000Z","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":172,"title":"Test if a Number is a Palindrome without using any String Operations","description":"*Description*\r\n\r\nGiven an integer _X_, determine if it is a palindrome number. That is, _X_ is equal to the _X_ with the digits reversed (with no leading 0s). The twist is that your code cannot use any function or variable name that has either \"str\", \"eval\", \"flip\" or \"printf\" in it.\r\n\r\n*Example*\r\n\r\n    X = 123454321;\r\n    Y = true;\r\n\r\n    X = 1234;\r\n    Y = false;","description_html":"\u003cp\u003e\u003cb\u003eDescription\u003c/b\u003e\u003c/p\u003e\u003cp\u003eGiven an integer \u003ci\u003eX\u003c/i\u003e, determine if it is a palindrome number. That is, \u003ci\u003eX\u003c/i\u003e is equal to the \u003ci\u003eX\u003c/i\u003e with the digits reversed (with no leading 0s). The twist is that your code cannot use any function or variable name that has either \"str\", \"eval\", \"flip\" or \"printf\" in it.\u003c/p\u003e\u003cp\u003e\u003cb\u003eExample\u003c/b\u003e\u003c/p\u003e\u003cpre\u003e    X = 123454321;\r\n    Y = true;\u003c/pre\u003e\u003cpre\u003e    X = 1234;\r\n    Y = false;\u003c/pre\u003e","function_template":"function y = isNumPalindrome(x)\r\n  y = true;\r\nend","test_suite":"%%\r\nx = 122131221;\r\ny_correct = true;\r\nassert( isequal(isNumPalindrome(x),y_correct) \u0026\u0026 isempty(regexp(evalc('type isNumPalindrome'),'(str|printf|eval|flip|dec2base)')) )\r\n\r\n%%\r\nx = 1221;\r\ny_correct = true;\r\nassert( isequal(isNumPalindrome(x),y_correct) \u0026\u0026 isempty(regexp(evalc('type isNumPalindrome'),'(str|printf|eval|flip|dec2base)')) )\r\n\r\n%%\r\nx = 12345;\r\ny_correct = false;\r\nassert( isequal(isNumPalindrome(x),y_correct) \u0026\u0026 isempty(regexp(evalc('type isNumPalindrome'),'(str|printf|eval|flip|dec2base)')) )\r\n\r\n%%\r\nx = 9849;\r\ny_correct = false;\r\nassert( isequal(isNumPalindrome(x),y_correct) \u0026\u0026 isempty(regexp(evalc('type isNumPalindrome'),'(str|printf|eval|flip|dec2base)')) )","published":true,"deleted":false,"likes_count":4,"comments_count":2,"created_by":134,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":255,"test_suite_updated_at":"2012-04-18T18:19:32.000Z","rescore_all_solutions":false,"group_id":38,"created_at":"2012-01-30T05:24:23.000Z","updated_at":"2026-03-31T17:41:42.000Z","published_at":"2012-01-30T05:39:05.000Z","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:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eDescription\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\u003eGiven an integer\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:i/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eX\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e, determine if it is a palindrome number. That is,\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:i/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eX\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e is equal to the\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:i/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eX\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e with the digits reversed (with no leading 0s). The twist is that your code cannot use any function or variable name that has either \\\"str\\\", \\\"eval\\\", \\\"flip\\\" or \\\"printf\\\" in it.\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:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\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[    X = 123454321;\\n    Y = true;\\n\\n    X = 1234;\\n    Y = false;]]\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":{"errors":[],"problems":[{"id":172,"title":"Test if a Number is a Palindrome without using any String Operations","description":"*Description*\r\n\r\nGiven an integer _X_, determine if it is a palindrome number. That is, _X_ is equal to the _X_ with the digits reversed (with no leading 0s). The twist is that your code cannot use any function or variable name that has either \"str\", \"eval\", \"flip\" or \"printf\" in it.\r\n\r\n*Example*\r\n\r\n    X = 123454321;\r\n    Y = true;\r\n\r\n    X = 1234;\r\n    Y = false;","description_html":"\u003cp\u003e\u003cb\u003eDescription\u003c/b\u003e\u003c/p\u003e\u003cp\u003eGiven an integer \u003ci\u003eX\u003c/i\u003e, determine if it is a palindrome number. That is, \u003ci\u003eX\u003c/i\u003e is equal to the \u003ci\u003eX\u003c/i\u003e with the digits reversed (with no leading 0s). The twist is that your code cannot use any function or variable name that has either \"str\", \"eval\", \"flip\" or \"printf\" in it.\u003c/p\u003e\u003cp\u003e\u003cb\u003eExample\u003c/b\u003e\u003c/p\u003e\u003cpre\u003e    X = 123454321;\r\n    Y = true;\u003c/pre\u003e\u003cpre\u003e    X = 1234;\r\n    Y = false;\u003c/pre\u003e","function_template":"function y = isNumPalindrome(x)\r\n  y = true;\r\nend","test_suite":"%%\r\nx = 122131221;\r\ny_correct = true;\r\nassert( isequal(isNumPalindrome(x),y_correct) \u0026\u0026 isempty(regexp(evalc('type isNumPalindrome'),'(str|printf|eval|flip|dec2base)')) )\r\n\r\n%%\r\nx = 1221;\r\ny_correct = true;\r\nassert( isequal(isNumPalindrome(x),y_correct) \u0026\u0026 isempty(regexp(evalc('type isNumPalindrome'),'(str|printf|eval|flip|dec2base)')) )\r\n\r\n%%\r\nx = 12345;\r\ny_correct = false;\r\nassert( isequal(isNumPalindrome(x),y_correct) \u0026\u0026 isempty(regexp(evalc('type isNumPalindrome'),'(str|printf|eval|flip|dec2base)')) )\r\n\r\n%%\r\nx = 9849;\r\ny_correct = false;\r\nassert( isequal(isNumPalindrome(x),y_correct) \u0026\u0026 isempty(regexp(evalc('type isNumPalindrome'),'(str|printf|eval|flip|dec2base)')) )","published":true,"deleted":false,"likes_count":4,"comments_count":2,"created_by":134,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":255,"test_suite_updated_at":"2012-04-18T18:19:32.000Z","rescore_all_solutions":false,"group_id":38,"created_at":"2012-01-30T05:24:23.000Z","updated_at":"2026-03-31T17:41:42.000Z","published_at":"2012-01-30T05:39:05.000Z","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:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eDescription\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\u003eGiven an integer\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:i/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eX\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e, determine if it is a palindrome number. 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The twist is that your code cannot use any function or variable name that has either \\\"str\\\", \\\"eval\\\", \\\"flip\\\" or \\\"printf\\\" in it.\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:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\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[    X = 123454321;\\n    Y = true;\\n\\n    X = 1234;\\n    Y = false;]]\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\\\" 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