{"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":44788,"title":"Find the right number make the equation","description":"Given positive integer number n, find the right positive integer number a, b , so that\r\n\r\n(1) sqrt(a + n * b) is a positive integer number\r\n\r\n(2) sqrt(hypot(a,b)) is a positive integer number\r\n\r\nNote: the output must be char array!\r\n\r\nHave fun!","description_html":"\u003cp\u003eGiven positive integer number n, find the right positive integer number a, b , so that\u003c/p\u003e\u003cp\u003e(1) sqrt(a + n * b) is a positive integer number\u003c/p\u003e\u003cp\u003e(2) sqrt(hypot(a,b)) is a positive integer number\u003c/p\u003e\u003cp\u003eNote: the output must be char array!\u003c/p\u003e\u003cp\u003eHave fun!\u003c/p\u003e","function_template":"function y = find_right_number_for_F(x)\r\n  y = x;\r\nend","test_suite":"%% 1\r\nfid = fopen('exact_sqrt.p','wb');\r\nfwrite(fid,sscanf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x'));\r\nfclose(fid);\r\n\r\n%% 2\r\nfor n = 1 : 3\r\n    [a, b] = find_right_number_for_F(n);\r\n    assert(ischar(a));\r\n    assert(ischar(b));\r\n    a = java.math.BigInteger(a);\r\n    b = java.math.BigInteger(b);\r\n    c = 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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\u003eGiven positive integer number n, find the right positive integer number a, b , so that\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\u003e(1) sqrt(a + n * b) is a positive integer number\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\u003e(2) sqrt(hypot(a,b)) is a positive integer number\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle 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fopen('exact_sqrt.p','wb');\r\nfwrite(fid,sscanf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x'));\r\nfclose(fid);\r\n\r\n%% 2\r\nfor n = 1 : 3\r\n    [a, b] = find_right_number_for_F(n);\r\n    assert(ischar(a));\r\n    assert(ischar(b));\r\n    a = java.math.BigInteger(a);\r\n    b = java.math.BigInteger(b);\r\n    c = 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