You are given 3 parameters: int U, int L, and array C containing n ints. Find a matrix with 2 rows and n columns where:
– Each element is either 1 or 0.
– The sum of ints in the upper row is U.
– The sum of ints in the lower row is L.
– C is an array of ints of length n, where the sum of ints in k-th column is C[k].
Convert each matching matrix to a comma separated string and return them in an array. If there is no match, return “IMPOSSIBLE”.
For example, given:<\/p>\n\n\n\n
U = 2\nL = 2\nC = [2, 0, 2, 0]<\/pre>\n\n\n\nIts only valid matrix and result is:<\/p>\n\n\n\n
1 0 1 0\n1 0 1 0\n\n[ \"1010,1010\" ]<\/pre>\n\n\n\nTo solve, simply increment through ints, convert them to binary arrays, and compare sums. Since C is of length n, the range of numbers to check is 0 to 2^n – 1.<\/p>\n\n\n\n
function solution(U, L, C) {\n const max = Math.pow(2, C.length)\n const matches = []\n\n for (let upper = 0; upper < max; upper++) {\n let upperArray = intToBinaryArray(upper, C.length)\n\n if (!isBitSumEqual(upperArray, U))\n continue\n\n for (let lower = 0; lower < max; lower++) {\n let lowerArray = intToBinaryArray(lower, C.length)\n\n if (!isBitSumEqual(lowerArray, L))\n continue\n\n if (isMatch(upperArray, lowerArray, U, L, C))\n matches.push(${upperArray.join("")},${lowerArray.join("")}<\/code>)\n }\n }\n\n if (matches.length > 0)\n return matches\n\n return \"IMPOSSIBLE\"\n}\n\nfunction isMatch(upperArray, lowerArray, U, L, C) {\n for (let i = 0; i < C.length; i++) {\n let u = upperArray[i]\n let l = lowerArray[i]\n let c = C[i]\n\n if (u + l != c)\n return false\n }\n\n if (!isBitSumEqual(upperArray, U))\n return false\n\n if (!isBitSumEqual(lowerArray, L))\n return false\n\n return true\n}\n\nfunction isBitSumEqual(array, sum) {\n let total = 0\n\n for (let i = 0; i < array.length; i++) {\n total += array[i]\n }\n\n return (total == sum)\n}\n\nfunction intToBinaryArray(n, length) {\n let binary = n.toString(2)\n let binaryPadded = binary.padStart(length, '0')\n let binStringArray = binaryPadded.split(\"\")\n let binIntArray = binStringArray.map(Number)\n return binIntArray\n}\n\nlet U = 2\nlet L = 2\nlet C = [2,0,2,0]\n\nconsole.log(U: ${U} L: ${L} C: ${C}<\/code>)\nlet result = solution(U, L, C)\nconsole.log(result)\n\nU = 3\nL = 2\nC = [2,1,1,0,1]\n\nconsole.log(U: ${U} L: ${L} C: ${C}<\/code>)\nresult = solution(U, L, C)\nconsole.log(result)\n\n\nU: 2 L: 2 C: 2,0,2,0\n[ '1010,1010' ]\nU: 3 L: 2 C: 2,1,1,0,1\n[ '10101,11000', '11001,10100', '11100,10001' ]<\/pre>\n","protected":false},"excerpt":{"rendered":"You are given 3 parameters: int U, int L, and array C containing n ints. Find a matrix with 2 rows and n columns where:– Each element is either 1 or 0.– The sum of ints in the upper row is U.– The sum of ints in the lower row is L.– C is an […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":2,"menu_order":24,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"_links":{"self":[{"href":"https:\/\/resrvoir.com\/index.php?rest_route=\/wp\/v2\/pages\/1185"}],"collection":[{"href":"https:\/\/resrvoir.com\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/resrvoir.com\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/resrvoir.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/resrvoir.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1185"}],"version-history":[{"count":39,"href":"https:\/\/resrvoir.com\/index.php?rest_route=\/wp\/v2\/pages\/1185\/revisions"}],"predecessor-version":[{"id":1247,"href":"https:\/\/resrvoir.com\/index.php?rest_route=\/wp\/v2\/pages\/1185\/revisions\/1247"}],"up":[{"embeddable":true,"href":"https:\/\/resrvoir.com\/index.php?rest_route=\/wp\/v2\/pages\/2"}],"wp:attachment":[{"href":"https:\/\/resrvoir.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1185"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}