ulam_dist.py

import turtle
import math

# даны 2 числа, берем 2 ближайшие к ним точки на ковре улама, считаем кратчайший путь

def prime(n):
    if n == 2:
        return True
    if n % 2 == 0 or n <= 1:
        return False

    sqr = int(math.sqrt(n)) + 1

    for divisor in range(3, sqr, 2):
        if n % divisor == 0:
            return False
    return True

def dist(x, y):
    return math.sqrt((x[0] - y[0]) ** 2 + (x[1] - y[1]) ** 2)

def find_nearest(x, ps):
    min_dist = 10**100
    min_p = None
    for p in ps:
        d = dist(x, p)
        if d < min_dist and p != x:
            min_p = p
            min_dist = d
    return min_p

# draw triangle intersecting points (a, 0) and (0, b)
a, b = 50, 50

turtle.setup(a * 2, b * 2)
t = turtle.Turtle()
t.penup()
t.speed(0)

def tprint(s):
    t.write(s, align="center", font=("Arial", 12, "normal"))

def tlogpos(s):
    cells[s] = (int(t.xcor()), int(t.ycor()))

alpha = 1
beta = 2
a = 0
b = 0
start = 12
end = 99
tprint("O")
cells = {}
for i in range(150):
    a += 1
    if i == start :
        tprint("s")
        tlogpos("s")
    elif i == end :
        tprint("e")
        tlogpos("e")
    elif prime(i):
        tprint("⬛")
        tlogpos(str(i))
    t.forward(40)
    if a == alpha:
        a = 0
        b = (b + 1) % beta
        alpha += (b - 1) % beta
        t.left(90)
x1 = find_nearest(cells["s"], cells.values())
x2 = find_nearest(cells["e"], cells.values())
t.goto(x1)
t.pencolor("red")
t.pendown()
t.goto(x2)
t.penup()
tprint("ulam ditance = " + str(int(dist(x1, x2))))

#input("Press Enter to exit...")