How to double each control variable in for loop in python

I want to implement a loop body like this in the cPP/ Java language: 

for(auto i = 0; i < N; i += i) {
    //do something;
}

but I try to do this in python: 

for i in range(0, N, i)
    -sharpdo something

the interpreter reminds me

undefined name "i"
Python
Sep.27,2021

after thinking about it, write two first.

the initial I value of your cycle cannot be 0. 

""" 1While """
i = 1
N = 50
while True:
    -sharp do something
    print("i = ", i)
    i += i
    if i >= N:
        break


""" 2 """
def gen(i, N):
    for index in range(i,N+1):
        -sharp 0,1,
        if index == i:
            yield index
            i += i
            
def gen2(i, N):
    while True:
        if i > N:
            break
        yield i
        i += i

-sharp gen  gen2 ,

-sharp i  N  1  10
for index in gen(1, 10):
    -sharp do something
    print(index)

-sharp i  N  3  50
for index in gen2(3, 50):
    -sharp do something
    print(index)

the first one uses the While True dead loop, in which the judgment logic jumps out of the loop.

the second one uses a generator, which is actually good to write this way. I prefer the second one, which looks better.

both ideas are the same, but they are written differently.

Let's talk about other implementations. I think it's enough. 

for i in(2**e for e in range(N)):
    print(i)
    -sharp do something

Previous: WeChat Mini Programs video component using poster to set the cover image has no effect?

Next: How to put the written front-end page into springboot

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
© 2021 CodesHelper
Advertising Contact us About us
Menu