Function that returns a list of m integers that sums n

random_bins_in_balls.py

import random

def random_balls_in_bins(balls, bins):
    """
    Returns a list of <bins> integers that sum <balls>

    We can think this as a problem of bosons:
    
    We have to distribute balls in bins. To model this, we use a shuffle of
    
    'o' * balls + '|' * (bins-1)
    
    This results in a string of the form oo|ooo|oo where we leave the last '|' fixed
    
    Parameters:
    ----------
    
    balls: int > 0
        number of balls to distribute
    bins: int > 0
        number of bins 
        
    Returns
    -------
    
    A list of <bins> integers that sum <balls>
    """
    balls_and_bins = list('o' * balls + '|' * (bins-1))
    random.shuffle(balls_and_bins)

    bins = []
    current = 0
    
    for e in balls_and_bins:
        if e == 'o':
            current +=1
        elif e == '|':
            bins.append(current)
            current = 0

    bins.append(current)
    
    return bins