'''A program demonstrating the performance benefit
of using a set over a list.
Author: Sean Barker, CSCI 1101B'''

from time import perf_counter
import sys

# number of searches in a single experiment
NUM_TRIALS = 1000

def run_trials(collection):
    '''Repeatedly search the given collection (either a list or set) 
    for numbers using the 'in' operator.'''
        
    # record the current time
    t_start = perf_counter()

    # run the set of trials
    for i in range(NUM_TRIALS):
        trial_result = i in collection # search for a number in the list/set
            
    # calculate how long the trials took
    duration = perf_counter() - t_start
    print('Trials took {0:2f} msec\n'.format(duration * 1000))
    
    # display output immediately (don't worry about this line)
    sys.stdout.flush()       


def main():
    '''Prompt the user for a number of elements, then run a set of
    search trials using a list, then a set.'''
    
    finished = False
    while not finished:
        num_items_str = input('Enter the number of elements to test: ')
        if num_items_str == 'quit':
            finished = True
        else:
            num_items = int(num_items_str)
            
            print('Running trials using list...')
            nums_list = [0] * num_items
            run_trials(nums_list)
            
            print('Running trials using set...')            
            nums_set = set([0] * num_items)
            run_trials(nums_set)
            
            
main()