# 3-6-9 in Python

Suppose we have a number n, we have to construct a list with each number from 1 to n, except when it is multiple of 3 or has a 3, 6, or 9 in the number, it should be the string "no-fill".

So, if the input is like 20, then the output will be ['1', '2', 'clap', '4', '5', 'clap', '7', '8', 'clap', '10', '11', 'clap', 'clap', '14', 'clap', 'clap', '17', 'clap', 'clap', '20']

To solve this, we will follow these steps −

• string := "no-fill"

• ls:= make a list of numbers as string from 1 to n

• for i in range 0 to size of ls - 1, do

• if ls[i] is divisible by 3, then

• ls[i]:= string

• otherwise when '3' is present in ls[i], then

• ls[i]:= string

• otherwise when '6' is present in ls[i], then

• ls[i]:= string

• otherwise when '9' is present in ls[i], then

• ls[i]:= string

• return ls

Let us see the following implementation to get better understanding −

## Example

Live Demo

class Solution:
def solve(self, n):
string = "no-fill"
ls=[str(i) for i in range(1,n+1)]
for i in range(len(ls)):
if int(ls[i])%3==0:
ls[i]=string
elif '3' in ls[i]:
ls[i]=string
elif '6' in ls[i]:
ls[i]=string
elif '9' in ls[i]:
ls[i]=string
return ls
ob = Solution()
print(ob.solve(20))

## Input

20

## Output

['1', '2', 'clap', '4', '5', 'clap', '7', '8', 'clap', '10', '11', 'clap', 'clap', '14', 'clap', 'clap', '17', 'clap', 'clap', '20']