how to select random names from list without repitition in python
I have to random choose names from a list in python using random.randint.
I have done it so far. but i am unable to figure out how to print them without repetition. some of the name repeat them after 10 to 15 names.
please help me out. I am not allowed to use any high functions. I should do it with simple functions. here is my program.
import random
names = [about 150 names]
print([names[random.randint(0, len(names)-1)] for i in range(user_input)])
Answer
If you can destructively modify names, just pop the values instead of copying them. Then they're not there anymore, so you won't be able to repeat.
If you can't destructively modify names, just do the same to a copy:
tmp = names[:]
result = [tmp.pop(random.randrange(len(tmp))) for _ in range(user_input)]
This does have quadratic performance, since each pop from the middle of the list has to shift half the list up one notch. But for 150 names, this is unlikely to be a problem. For example, on my laptop, picking 100 values out of 150 names takes 83 microseconds.
If you really aren't allowed to use even randrange, you can write it yourself:
def randrange(x): return randint(0, x-1)