Project Euler 008 – JavaScript

25 03 2011

Problem 8

Find the greatest product of five consecutive digits in the 1000-digit number.

73167176531330624919225119674426574742355349194934
96983520312774506326239578318016984801869478851843
85861560789112949495459501737958331952853208805511
12540698747158523863050715693290963295227443043557
66896648950445244523161731856403098711121722383113
62229893423380308135336276614282806444486645238749
30358907296290491560440772390713810515859307960866
70172427121883998797908792274921901699720888093776
65727333001053367881220235421809751254540594752243
52584907711670556013604839586446706324415722155397
53697817977846174064955149290862569321978468622482
83972241375657056057490261407972968652414535100474
82166370484403199890008895243450658541227588666881
16427171479924442928230863465674813919123162824586
17866458359124566529476545682848912883142607690042
24219022671055626321111109370544217506941658960408
07198403850962455444362981230987879927244284909188
84580156166097919133875499200524063689912560717606
05886116467109405077541002256983155200055935729725
71636269561882670428252483600823257530420752963450

Solution

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"&gt;

<html xmlns="http://www.w3.org/1999/xhtml"&gt;

<head>

    <title>Project Euler 008</title>

</head>

<body>

    <script type="text/javascript">

        dgts = "73167176531330624919225119674426574742355349194934" +

                 "96983520312774506326239578318016984801869478851843" +

                 "85861560789112949495459501737958331952853208805511" +

                 "12540698747158523863050715693290963295227443043557" +

                 "66896648950445244523161731856403098711121722383113" +

                 "62229893423380308135336276614282806444486645238749" +

                 "30358907296290491560440772390713810515859307960866" +

                 "70172427121883998797908792274921901699720888093776" +

                 "65727333001053367881220235421809751254540594752243" +

                 "52584907711670556013604839586446706324415722155397" +

                 "53697817977846174064955149290862569321978468622482" +

                 "83972241375657056057490261407972968652414535100474" +

                 "82166370484403199890008895243450658541227588666881" +

                 "16427171479924442928230863465674813919123162824586" +

                 "17866458359124566529476545682848912883142607690042" +

                 "24219022671055626321111109370544217506941658960408" +

                 "07198403850962455444362981230987879927244284909188" +

                 "84580156166097919133875499200524063689912560717606" +

                 "05886116467109405077541002256983155200055935729725" +

                 "71636269561882670428252483600823257530420752963450";

        answer = 0;

        for (i = 0; i < dgts.length – 5; i++) {

            product = dgts[i]*dgts[i+1]*dgts[i+2]*dgts[i+3]*dgts[i+4];

            if (product > answer) {

                answer = product;

            }

        }

        document.write("<b>" + answer + "</b>");

    </script>

</body>

</html>

Discussion

Voila.

If you have any questions, leave a comment, find me on Twitter (@azzlsoft) or email (rich@azzlsoft.com).