pyParetoPrinciple

# The Pareto Principle
# A number of players start with 100 dollars each
# A coin-toss between randomly chosen players results in payment of 10 from loser to winner
# Any player whose balance reduces to zero is eliminated and takes no further part
# Eventually only one player has any money left (has all the money) and is the overall winner
import random
num = 20                # Number of players
leadscore = 0
ctrtoss = 0
# Define 1 dummy slot (0) and 'num' slots for players 1 to num containing 100 dollars each
moneylist = [0] + [100] * num
while True:
    ctrtoss += 1        # Count number of coin tosses
    # Build a list of active players, being indexes of non-empty slots in moneylist
    activelist = [x for x in range(num+1) if moneylist[x]]
    ctr = len(activelist)       # Number of active players
    # Choose Winner randomly
    ra = random.randint(0, ctr-1)       # Pick a random index into the active list
    a = activelist[ra]                  # Get the coin-toss winning Player number
    # Choose loser (b) randomly, but not same as a
    b = a
    while b == a:
        rb = random.randint(0, ctr-1)   # Pick a random index into the active list
        b = activelist[rb]              # Get the coin-toss losing Player number
    moneylist[b] -= 10           # coin-toss loser loses 10 dollars
    moneylist[a] += 10           # coin-toss winner gains 10 dollars
    if moneylist[b] == 0:
        print("Player", b, "has run out of money and is eliminated")
    if moneylist[a] > leadscore:
        leadscore = moneylist[a]
        print("Player", a, "is leading with", leadscore, "in the bank")
        if leadscore >= num * 100:
            break
print("The winner is player", a, "after", ctrtoss, "tosses of the coin")