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 code used:
OneThousandRandom = "73167....63450" 'used the large block of one thousand numbers above on one line.. truncated here to save space
For i = 0 To 994
TextWindow.WriteLine("")
TextWindow.WriteLine("")
CurrentColumn = i
j = 0
For j = 0 To 4
Array.SetValue("Numbers",j+1,Text.GetSubText(OneThousandRandom,CurrentColumn+j,1))
EndFor
Check()
EndFor
Sub Check
CurrentNumber = Array.GetValue("Numbers",1) * Array.GetValue("Numbers",2) * Array.GetValue("Numbers",3) * Array.GetValue("Numbers",4) * Array.GetValue("Numbers",5)
TextWindow.WriteLine(CurrentNumber)
If( CurrentNumber > BiggestNumber ) Then
BiggestNumber = CurrentNumber
EndIf
EndSub
TextWindow.WriteLine(BiggestNumber)The above code works, but is very inefficient in nature, as it gets 5 numbers, multiplies them, and then checks it against another number. However, the problem can be solved in another manner, looking for the largest 5 digit number within the string, that does not contain a zero, then multiplying each number within.
Here's another solution for the same problem. You only compute the product once.
numPool = "7316717...3450" ' Number trimmed here
length = 1000
maxNumber = 0
For i = 0 To length - 5
subNumber = Text.GetSubText(numPool, i, 5)
containsZero = Text.IsSubText(subNumber, "0")
If containsZero = "False" And subNumber > maxNumber Then
maxNumber = subNumber
EndIf
EndFor
product = 1
For i = 0 To 4
product = product * Text.GetSubText(maxNumber, i, 1)
EndFor
TextWindow.WriteLine("Max Product = " + product)