素数ゼミのシミュレーション. 同じ年に羽化した個体がランダムに2匹組み合わさって２匹の子供を残す. ある年に生まれる子孫は同じ年数幼生で過ごす様にはなるが、１つの種類しか生き残らない

cicada.py

#!/usr/bin/python


import heapq
from random import randint, shuffle

import sys
import os


def crossbreed(c, d, n):
    "cicada"
    for i in range(n):
        if c < d:
            yield randint(c, d)
        elif c == d:
            yield c
        elif d < c:
            yield randint(d, c)


def randpop2(xs):
    shuffle(xs)
    while len(xs) > 1:
        a = xs.pop()
        b = xs.pop()
        yield a, b


class World:
    def __init__(self):
        self.cicadas = {}
        self.year = 0

        for c in crossbreed(2, 30, 100):
            self.add(c, c)

    def report(self):
        xs = self.cicadas.items()
        sorted(xs, key=lambda x:x[0])
        for y, cicada in xs:
            print y, cicada

    def add(self, y, c):
        xs = self.cicadas.get(y, None)
        if xs is None:
            xs = []
        xs.append(c)
        self.cicadas[y] = xs

    def do_year(self):
        wakeup = self.cicadas.get(self.year, None)
        if wakeup is None:
            return
        del self.cicadas[self.year]

        for a, b in randpop2(wakeup):
            for c in crossbreed(a, b, 2):
                self.add(self.year + c, c)

    def run(self, until):
        while self.year < until:
            self.do_year()
            self.year += 1



w = World()

w.run(100)
w.report()