Python程序输出数字后跟 'L'

Question

我用Python创建了一个程序来生成斐波那契或卢卡斯数序列中任意数量的元素(斐波那契是1,1,2,3,5,8,13等，卢卡斯是2,1,3,4 ,7,11,18 等)，但由于某种原因，每当我针对特定数字(似乎高于某个阈值)运行它时，它都会输出该数字，后跟大写 L。它执行此操作的第一个数字是 2971215073，但其他程序生成的数字远远高于没有问题的数字。我该如何阻止它这样做？完整代码:

import time
f = [1,1]
l = [2,1]
x = True
while x == True:
    b = raw_input('Would you like to generate fibonacci numbers (enter f) or lucas numbers (enter l)?\n')
    if b == 'l' or b == 'L' or b == 'lucas' or b == 'Lucas':
        z = True
        x = False
    elif b == 'f' or b == 'F' or b == 'fibonnaci' or b == 'Fibonnaci' or b == 'Fibonacci' or b == 'fibonacci':
        z = False
        x = False
    else:
        print 'That isn\'t an answer. Enter f or l.'
y = True
while y == True:
    c = raw_input('Would you like to generate up to a limit (enter a) or a certain number of elements (enter b)?\n')
    if c == 'A' or c == 'a':
        w = True
        y = False
    elif c == 'B' or 'b':
        w = False
        y = False
    else:
        print 'That isn\'t an answer. Enter a or b.'
a = input('Enter an upper bound.\n')
c = 1
if z == True and w == True:
    start = time.clock()
    while((l[c] + l[c-1]) <= a):
        l += [(l[c] + l[c-1])]
        c += 1
    print l
    if (time.clock() - start) >= 60:
        print 'Program took ' + str(time.clock() - start) + ' seconds to run.'
if z == True and w == False:
    start = time.clock()
    while(c-1 <= a-3):
        l += [(l[c] + l[c-1])]
        c += 1
    print l
    if (time.clock() - start) >= 60:
        print 'Program took ' + str(time.clock() - start) + ' seconds to run.'
if z == False and w == True:
    start = time.clock()
    while((f[c] + f[c-1]) <= a):
        f += [(f[c] + f[c-1])]
        c += 1
    print f
    if (time.clock() - start) >= 60:
        print 'Program took ' + str(time.clock() - start) + ' seconds to run.'
if z == False and w == False:
    start = time.clock()
    while(c-1 <= a-3):
        f += [(f[c] + f[c-1])]
        c += 1
    print f
    if (time.clock() - start) >= 60:
        print 'Program took ' + str(time.clock() - start) + ' seoonds to run.'
raw_input('Press enter to exit.')

输出示例:

Would you like to generate fibonacci numbers (enter f) or lucas numbers (enter l)?
f
Would you like to generate up to a limit (enter a) or a certain number of elements (enter b)?
b
Enter an upper bound.
100



  [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597,
 2584, 4181, 6765, 10946, 17711, 28657, 46368, 75025, 121393, 196418, 317811,
     514229, 832040, 1346269, 2178309, 3524578, 5702887, 9227465, 14930352,
     24157817, 39088169, 63245986, 102334155, 165580141, 267914296, 433494437, 701408733, 1134903170, 1836311903, 2971215073L, 4807526976L, 7778742049L,
     12586269025L, 20365011074L, 32951280099L, 53316291173L, 86267571272L,
     139583862445L, 225851433717L, 365435296162L, 591286729879L, 956722026041L, 1548008755920L, 2504730781961L, 4052739537881L, 6557470319842L, 
    10610209857723L, 17167680177565L, 27777890035288L, 44945570212853L, 
    72723460248141L, 117669030460994L, 190392490709135L, 308061521170129L, 
    498454011879264L, 806515533049393L, 1304969544928657L, 2111485077978050L,
     3416454622906707L, 5527939700884757L, 8944394323791464L, 14472334024676221L,
     23416728348467685L, 37889062373143906L, 61305790721611591L, 
    99194853094755497L, 160500643816367088L, 259695496911122585L, 420196140727489673L, 679891637638612258L, 1100087778366101931L, 1779979416004714189L, 2880067194370816120L, 4660046610375530309L,
     7540113804746346429L, 12200160415121876738L, 19740274219868223167L,
     31940434634990099905L, 51680708854858323072L, 83621143489848422977L,
     135301852344706746049L, 218922995834555169026L, 354224848179261915075L]
        Press enter to exit.

Answer 1

L 是 Python 2 的一个怪癖，表示“长整数”。如果单独打印数字(而不是打印列表)，则不会有“L”。另一种选择是升级到 Python 3，它消除了这个怪癖。

考虑更换:

print l

与

print ", ".join(str(x) for x in l)

如果您仍然需要方括号，那么您可以使用格式:

print "[{}]".format(", ".join(str(x) for x in l))