将列表中的索引计数为x number python

Question

我有一个这样的列表，从0到1000。

x = ['0_1','0_2','0_3' ..., '1000_1','1000_2','1000_3']

每当索引中的字符变化时，我都需要对它进行计数，如下所示。

list_leng = len(x)

for i in range(0, list_leng): y = x[i] z = y[0] print this should iterate through all the list and only print when the z number changes ' # how should I make it print '

Answer 1

如果我理解你的问题，答案必须是这样的;

comparisonText = ""
for each in x:
    preNumber = each.split('_')[0]
    if comparisonText != preNumber:
        print preNumber, 'is different than previous.'
        comparisonText = preNumber #change the comparisonText