#!/usr/bin/env python
# coding: utf-8

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import random as rd


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def sons(numbers):
    """propagating sons down the generations"""
    sons = 0
    for i in range(numbers):
        rand = rd.random()
        if (rand < 0.3):
            branch = 0
        elif (rand < 0.7):
            branch = 1
        elif (rand < 1.0):
            branch = 2
        sons = sons + branch
    return sons


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survivors = []
for i in range(1001):
    males = 1
    for i in range(101):
        males = sons(males)
    survivors = survivors + [males]
print(survivors)


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