python programming

  #rolling a 6-face dice #calculate how many iterations needed to get 6 import random n=1 iterations=0 while n>0:     n=random.randint(1,6)     if n==6:         print("Total iterations# ",iterations)         break#exit loop     iterations+=1

  #Python 3.7.5 L=[10,10,2] i=0 while L[i:]:    i+=1 print("Length is ",i) #Likewise length of string  S="NAME" i=0 while S[i:]:     i+=1 print("len is ",i)

 If total time taken to calculate perfect numbers from 1 to 10000 is 12 seconds(on i5 2nd gen 12gb ram) then find out total time taken for perfect numbers from 1 to 20000? sol: 24 seconds is wrong  Because as the number becoming large, computation calculation increases there by delay in time So time is 54 seconds(in my system) #Find  all perfect number 1 -100 import time as t start=t.time() z=1 while z<=20000:     n=z     i=1     sum=0     while i<n:         if n%i==0:             sum=sum+i         i=i+1     if sum==n:         print(n, end="\t")     z=z+1 end=t.time() print("Total time #",end-start, " seconds")

def r(a):i=a.find('0');~i or exit(a);[m in[(i-j)%9*(i/9^j/9)*(i/27^j/27|i%9/3^j%9/3)or a[j]for j in range(81)]or r(a[:i]+m+a[i+1:])for m in'%d'%5**18] from sys import*;r(argv[1])   Src: http://www.scottkirkwood.com/2006/07/shortest-sudoku-solver-in-python.html Original Source:   Mark Byer's site has some more  Sudoku solvers     (can be found on web archive as web site is down) Expalanation https://jakevdp.github.io/blog/2013/04/15/code-golf-in-python-sudoku/ NOTE "A=0 #False B=20#True print(A or B) #B A=1 #True B=0#False print(A or B) #A you might expect the result to be either True or False. Instead, Python does something a bit clever. If the result is False, it returns A (which, naturally, evaluates to False).  If the result is True, it returns A if A evaluates to True, and B otherwise.  We can use this fact to remove the if statement completely from the set comprehension