如何在字符串中打印两个或多个相同的字母？

Question

I have a string "Hello JJ" I have to print this so that where the letters of the string that are next to each other and identical are printed on the same line. Like this.

0 
1 H
2 He
3 Hell
4 Hello
5 Hello
6 Hello JJ

I need to use the for loop . And the code I used this one.

text = 'Hello.'
for position in range(0, len(text)+1):  
    print position, text[0:position]

But how do I make it print the identical letters at the same time (like in line 3 and 6) ?

Answer 1

text = 'Hello JJ'
counter = 0
for i in range(len(text)):
    if counter:
        counter -= 1
        continue
    for j in range(i + 1, len(text)):
        if text[j] != text[i]: break
        else: counter += 1
    print text[0:i + counter + 1]

Output

H
He
Hell
Hello
Hello 
Hello JJ

Answer 2

>>> from itertools import groupby
>>> strs = "Hello JJ"
>>> start = ''
for k, g in groupby(enumerate(strs), key=lambda x:x[1]):
    lis = list(g)
    start += ''.join(x[1] for x in lis)
    print lis[0][0], start
...     
0 H
1 He
2 Hell
4 Hello
5 Hello 
6 Hello JJ

Answer 3

Using itertools.groupby() .

from itertools import groupby
groups = [''.join(l) for g,l in groupby("Hello JJ")]
for i in range(len(groups)+1):
    print ''.join(groups[:i])

>>> 

H
He
Hell
Hello
Hello 
Hello JJ

Answer 4

split text into a list of strings.

import re
text = "hello piithon"
items = [m.group() for m in re.finditer(r"(.)(\1*)",s)]
for position in range(0, len(text)+1):
    print position, items[0:position]

it should work.