如何在python中向左或向右移动东西？

Question

Having a problem, lets say I have this code (easiest possible):

n=5
j=3
for i in range(n):
    print("kurt")
for x in range(j):
    print("karl")

If I want this to be printed like a protocol, that is, I don't want them after each other, I want my second for-loop to be to the right of the first for-loop when I print it, like this:

kurt karl
kurt karl
kurt karl
kurt
kurt

Answer 1

Sure, just put them in one print statement.

Here I've told it to loop for the maximum number (in this case 5 ) and then if the loop has reached the minimum number ( 3 ) to stop printing the second one.

n = 5
j = 3
for i in range (max(n,j)):
    if i < min(n,j):
        print("kurt" + " " + "karl")
    else:
        print("kurt")

Answer 2

As I understood, you want to print the values of next loop in right of previous loop, you can achieve it by writing this:

In python 2.7

for i, k in zip(range(n), range(j)):
   print "kurt",
   print "karl"

In python 3.x

for i, k in zip(range(n), range(j)):
       print("kurt", end=" ")
       print("karl")

Answer 3

from itertools import izip_longest
first = ['kurt']*j
second = ['karl']*n
for l,r in  izip_longest(first ,second ):
   print l,r

output:

kurt karl
kurt karl
kurt karl
None karl
None karl

if you want white space.

from itertools import izip_longest
first = ['kurt']*j
second = ['karl']*n
spaceJ,spaceN = len(first [0]),len(second [0])
for l,r in  izip_longest(first ,second ):
   print l if l else ' '*spaceJ,
   print r if r else ' '*spaceN 

output

kurt karl
kurt karl
kurt karl
     karl
     karl

Answer 4

Assuming that this printing of "kurt" and "karl" is just an example of a more complex problem you're trying to solve, a general strategy for this sort of problem is to use Python generators to run the two loops concurrently, and then combine the results for output.

For example:

from itertools import zip_longest

n = 5
j = 3

def kurt():
    for i in range(n):
        yield "kurt"

def karl():
    for x in range(j):
        yield "karl"

for kurt_result, karl_result in zip_longest(kurt(), karl(), fillvalue=""):
    print(kurt_result, karl_result)

When a function body contains the yield keyword, Python produces a generator rather than a regular function. A generator will, when called, return an iterator that produces a value each time yield is called, and then waits until the next value is read before proceeding to the next yield . Once the generator function returns, the iteration ends.

The final for loop here then uses zip_longest , which is a utility function that takes two or more iterators and produces another iterator that yields the sequence of combinations of reading from all of the given iterators at once, allowing you to easily match up the corresponding results from each iterator.

This code then produces the following output:

kurt karl
kurt karl
kurt karl
kurt 
kurt 

(The above assumes Python 3. If you were using Python 2, the zip_longest function was then named izip_longest , so you'd need to adjust the two references.)