Easier way to do nested for loops?-CodePudding

So in a lot of my coding problems, I end up doing something along the lines of:

for i in range(10):
    for j in range(10):
        for k in range(10):
            print(i, j, k)

I was just wondering if there was a simpler way to iterate through multiple ranges of numbers? I want to have it so I can give an argument of 4 in my function and it iterates through 4 different numbers.

I know that:

for i, j in range(10):
    print(i, j)

will iterate through i and j at the same time.

Any help would be greatly appreciated!

CodePudding user response：

You can use itertools.product to do this, it will effectively write the nested loops for you, but it's not more efficient as far as I know, it's mostly just more convenient:

from itertools import product
for i, j, k in product(range(10), range(10), range(10)):
    print(i, j, k)

EDIT: As @interjay pointed out, the repeat= argument might also be useful to you. I assumed you might not always use the same iterator for i, j, and k, but your example can be simplified further like this:

for i, j, k in product(range(10), repeat=3):
    print(i, j, k)

The itertools module has lots of convenient ways to manipulate and combine iterators.

CodePudding user response：

Is this what you want?

def loop_fun(loop_number, *args):
    if loop_number:
        for i in range(10):
            loop_fun(loop_number-1, i, *args)
            if loop_number == 1:
                print(*args, i)


loop_fun(4)

CodePudding user response：

Is this what you want?

def loop_fun(loop_number, *args):
if loop_number:
    for i in range(10):
        loop_fun(loop_number-1, i, *args)
        if loop_number == 1:
            print(*args, i)