--- id: 5900f3ca1000cf542c50fedc title: 'Problem 93: Arithmetic expressions' challengeType: 5 forumTopicId: 302210 dashedName: problem-93-arithmetic-expressions --- # --description-- By using each of the digits from the set, {1, 2, 3, 4}, exactly once, and making use of the four arithmetic operations (+, −, \*, /) and brackets/parentheses, it is possible to form different positive integer targets. For example,
8 = (4 * (1 + 3)) / 2
14 = 4 * (3 + 1 / 2)
19 = 4 * (2 + 3) − 1
36 = 3 * 4 * (2 + 1)
Note that concatenations of the digits, like 12 + 34, are not allowed. Using the set, {1, 2, 3, 4}, it is possible to obtain thirty-one different target numbers of which 36 is the maximum, and each of the numbers 1 to 28 can be obtained before encountering the first non-expressible number. Find the set of four distinct digits, `a` < `b` < `c` < `d`, for which the longest set of consecutive positive integers, 1 to `n`, can be obtained, giving your answer as a string: `abcd`. # --hints-- `arithmeticExpressions()` should return a number. ```js assert(typeof arithmeticExpressions() === 'number'); ``` `arithmeticExpressions()` should return 1258. ```js assert.strictEqual(arithmeticExpressions(), 1258); ``` # --seed-- ## --seed-contents-- ```js function arithmeticExpressions() { return true; } arithmeticExpressions(); ``` # --solutions-- ```js // solution required ```