Question

我正在努力寻找13位连续数字的最大数字73167176531330624919225119674426574742355349194934 96983520312774506326239578318016984801869478851843 85861560789112949495459501737958331952853208805511 12540698747158523863050715693290963295227443043557 66896648950445244523161731856403098711121722383113 62229893423380308135336276614282806444486645238749 30358907296290491560440772390713810515859307960866 70172427121883998797908792274921901699720888093776 65727333001053367881220235421809751254540594752243 52584907711670556013604839586446706324415722155397 53697817977846174064955149290862569321978468622482 83972241375657056057490261407972968652414535100474 82166370484403199890008895243450658541227588666881 16427171479924442928230863465674813919123162824586 17866458359124566529476545682848912883142607690042 24219022671055626321111109370544217506941658960408 07198403850962455444362981230987879927244284909188 84580156166097919133875499200524063689912560717606 05886116467109405077541002256983155200055935729725 71636269561882670428252483600823257530420752963450。

但是，我的代码似乎在某处出错，输出987次如下： 0 731671765313 以下是有问题的代码：

num = str('**insert the big number here**')
highest = 0
mylist=[]
for i in range(987):
    n = 0
    m = 12
    product = 1
    mylist=[num[n:m]]
    for x in mylist:
        product *= x
        print(n, product)
    n += 1
    m += 1

任何帮助表示赞赏，因为我花了很长时间研究这个。

Answer 1

首先，正如所指出的，你需要将m和n移动到for循环之外，然后递增它们，而不是每次运行循环时将它们重置为相同的东西 - 重新检查相同的数字987次赢得＆＃39; t让你走得很远;）

但是请记住，对于切片，范围是从（包括）第一个索引到但不包括最后一个索引。试试吧：

string = '12345'
print(string[1:4])

--> 234

'5'位于第四个索引处，但未打印如果你想要n后的13位数，m实际上必须是 13 ，而不是12.这样，打印索引0到12，这是13位数。

最后，您可以添加一些代码来为您检查，而不是仅仅打印值，只有在结果高于其他值时才打印，如下所示

if product > highest:
    highest = product
    print('new largest product:', product)

祝Euler项目的其余部分好运！ :)

Answer 2

这里有几个问题。

num = str('**insert the big number here**')
highest = 0
# No need to declare mylist ahead of time
# Define n and m outside of loop:
n = 0
m = 13 # m should be 13
for i in range(987):
    product = 1
    mylist = num[n:m] # No extra [] here
    for x in mylist:
        product *= int(x) # x is string because num is string, so we must convert to int
    # Checking the product should be outside of the x loop:
    print(n, product)
    # Check if product is highest:
    if product > highest:
        highest = product
    n += 1
    m += 1

for循环返回结果直到结束（python）

2 个答案: