{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2026-06-05T00:10:21.000Z","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":"2026-06-05T00:00:00.000Z","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":1941,"title":"Lowest sum from a group of digits","description":"Hi there.  It's James's daughter here again, and my third grade math teacher is up to her old tricks.  This time, she's giving us an even number of digits between 0-9, and she wants us to come up with the smallest possible sum of two numbers that are the same length.\r\n\r\nFor example, if we're given [0 1 2 3], the smallest sum we can get using those numbers by adding two 2-digit numbers together is 33.  That's either 10+23 or 13+20.  We don't need to know what the two original numbers are, just what their sum is.  We also can't start any of our numbers with a zero, because that's cheating.\r\n\r\nYou guys did a great job with my earlier problems, and even taught my dad a few things about MATLAB!  I hope you can help me out with this one as well!","description_html":"\u003cp\u003eHi there.  It's James's daughter here again, and my third grade math teacher is up to her old tricks.  This time, she's giving us an even number of digits between 0-9, and she wants us to come up with the smallest possible sum of two numbers that are the same length.\u003c/p\u003e\u003cp\u003eFor example, if we're given [0 1 2 3], the smallest sum we can get using those numbers by adding two 2-digit numbers together is 33.  That's either 10+23 or 13+20.  We don't need to know what the two original numbers are, just what their sum is.  We also can't start any of our numbers with a zero, because that's cheating.\u003c/p\u003e\u003cp\u003eYou guys did a great job with my earlier problems, and even taught my dad a few things about MATLAB!  I hope you can help me out with this one as well!\u003c/p\u003e","function_template":"function y = lowest_number(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = 0:3; y_correct = 33; assert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx=[1 2 3 7 8 9] ; y_correct = 417; \r\nassert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx=[7 8 9 7 8 9] ; y_correct = 1578; \r\nassert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx = 0:9; y_correct = 34047; assert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx=7*[ones(1,5) zeros(1,7)]; y_correct=1400084; assert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx=[ones(1,8) zeros(1,10)]; y_correct=200000222; assert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx = [0:9 1:8]; y_correct = 225802467; assert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx=[randperm(10)-1 randperm(6)]; y_correct=22580247; assert(isequal(lowest_number(x),y_correct))\r\n","published":true,"deleted":false,"likes_count":7,"comments_count":3,"created_by":1615,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":56,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2013-10-17T16:55:16.000Z","updated_at":"2026-05-25T22:52:53.000Z","published_at":"2013-10-17T16:55:16.000Z","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\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"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\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\u003eHi there. It's James's daughter here again, and my third grade math teacher is up to her old tricks. This time, she's giving us an even number of digits between 0-9, and she wants us to come up with the smallest possible sum of two numbers that are the same length.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eFor example, if we're given [0 1 2 3], the smallest sum we can get using those numbers by adding two 2-digit numbers together is 33. That's either 10+23 or 13+20. We don't need to know what the two original numbers are, just what their sum is. We also can't start any of our numbers with a zero, because that's cheating.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eYou guys did a great job with my earlier problems, and even taught my dad a few things about MATLAB! I hope you can help me out with this one as well!\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":1941,"title":"Lowest sum from a group of digits","description":"Hi there.  It's James's daughter here again, and my third grade math teacher is up to her old tricks.  This time, she's giving us an even number of digits between 0-9, and she wants us to come up with the smallest possible sum of two numbers that are the same length.\r\n\r\nFor example, if we're given [0 1 2 3], the smallest sum we can get using those numbers by adding two 2-digit numbers together is 33.  That's either 10+23 or 13+20.  We don't need to know what the two original numbers are, just what their sum is.  We also can't start any of our numbers with a zero, because that's cheating.\r\n\r\nYou guys did a great job with my earlier problems, and even taught my dad a few things about MATLAB!  I hope you can help me out with this one as well!","description_html":"\u003cp\u003eHi there.  It's James's daughter here again, and my third grade math teacher is up to her old tricks.  This time, she's giving us an even number of digits between 0-9, and she wants us to come up with the smallest possible sum of two numbers that are the same length.\u003c/p\u003e\u003cp\u003eFor example, if we're given [0 1 2 3], the smallest sum we can get using those numbers by adding two 2-digit numbers together is 33.  That's either 10+23 or 13+20.  We don't need to know what the two original numbers are, just what their sum is.  We also can't start any of our numbers with a zero, because that's cheating.\u003c/p\u003e\u003cp\u003eYou guys did a great job with my earlier problems, and even taught my dad a few things about MATLAB!  I hope you can help me out with this one as well!\u003c/p\u003e","function_template":"function y = lowest_number(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = 0:3; y_correct = 33; assert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx=[1 2 3 7 8 9] ; y_correct = 417; \r\nassert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx=[7 8 9 7 8 9] ; y_correct = 1578; \r\nassert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx = 0:9; y_correct = 34047; assert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx=7*[ones(1,5) zeros(1,7)]; y_correct=1400084; assert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx=[ones(1,8) zeros(1,10)]; y_correct=200000222; assert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx = [0:9 1:8]; y_correct = 225802467; assert(isequal(lowest_number(x),y_correct))\r\n%%\r\nx=[randperm(10)-1 randperm(6)]; y_correct=22580247; assert(isequal(lowest_number(x),y_correct))\r\n","published":true,"deleted":false,"likes_count":7,"comments_count":3,"created_by":1615,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":56,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2013-10-17T16:55:16.000Z","updated_at":"2026-05-25T22:52:53.000Z","published_at":"2013-10-17T16:55:16.000Z","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\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"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\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\u003eHi there. It's James's daughter here again, and my third grade math teacher is up to her old tricks. This time, she's giving us an even number of digits between 0-9, and she wants us to come up with the smallest possible sum of two numbers that are the same length.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eFor example, if we're given [0 1 2 3], the smallest sum we can get using those numbers by adding two 2-digit numbers together is 33. That's either 10+23 or 13+20. We don't need to know what the two original numbers are, just what their sum is. We also can't start any of our numbers with a zero, because that's cheating.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eYou guys did a great job with my earlier problems, and even taught my dad a few things about MATLAB! I hope you can help me out with this one as well!\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":"Combinatorics III","count":1,"selected":false}],[{"value":"medium","count":1,"selected":false}]],"term":"tag:\"smallest sum\"","page":1,"per_page":50,"sort":"map(difficulty_value,0,0,999) asc"}}