diff --git a/Project-Euler/Problem8.js b/Project-Euler/Problem8.js new file mode 100644 index 0000000000..95e2ddd7f8 --- /dev/null +++ b/Project-Euler/Problem8.js @@ -0,0 +1,48 @@ +/* +Project Euler Problem 8: https://projecteuler.net/problem=8 +Largest product in a series +*/ + +// Get the number into an array +const grid = ` +73167176531330624919225119674426574742355349194934 +96983520312774506326239578318016984801869478851843 +85861560789112949495459501737958331952853208805511 +12540698747158523863050715693290963295227443043557 +66896648950445244523161731856403098711121722383113 +62229893423380308135336276614282806444486645238749 +30358907296290491560440772390713810515859307960866 +70172427121883998797908792274921901699720888093776 +65727333001053367881220235421809751254540594752243 +52584907711670556013604839586446706324415722155397 +53697817977846174064955149290862569321978468622482 +83972241375657056057490261407972968652414535100474 +82166370484403199890008895243450658541227588666881 +16427171479924442928230863465674813919123162824586 +17866458359124566529476545682848912883142607690042 +24219022671055626321111109370544217506941658960408 +07198403850962455444362981230987879927244284909188 +84580156166097919133875499200524063689912560717606 +05886116467109405077541002256983155200055935729725 +71636269561882670428252483600823257530420752963450 +`.trim().replace(/\n/g, "").split("") + +const x = 13 +let max = 0 + +function largestProduct () { + grid.forEach((str) => { + if (str.length < x) { + return + } + for (let i = 0, l = str.length; i <= l - x; i++) { + // substring() method returns the part of the string between the start and end indexes + const digits = str.substring(i, i + x).split('') + const product = digits.reduce((prod, c) => prod * parseInt(c), 1) + // update the max variable in case if our product is larger then max + if (product> max) max = product + } + }) + return max +} +console.log(largestProduct()) // output 23514624000

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