Drawing a 3×3 Magic Square with Python Turtle and Random Shuffle

The article demonstrates a simple approach to creating a 3×3 magic square visualization using Python. It first introduces the turtle library for drawing squares and provides a function zfx(a=200) that draws a single square of side length a.

Next, a helper function zfx2(a=100, x=0, y=0, c='gray', s='') is defined to position the turtle, fill the square with a specified color, and write a label at its center.

Using these helpers, the jgg(s='012345678') function draws the full 3×3 grid by calling zfx2 nine times with appropriate coordinates, colors, and characters from the input string.

To start, the grid can be displayed with placeholder symbols using jgg('?'*9).

The second part implements a brute‑force search for a valid magic square. It imports random, creates a list n = [1,2,3,4,5,6,7,8,9], and sets up a click handler run(x, y) that repeatedly shuffles n. After each shuffle it checks eight line‑sum conditions (rows, columns, diagonals) stored in real. If all conditions are true, the shuffled numbers are displayed with jgg(n) and the loop exits.

Finally, the program registers the click handler with w.onclick(run) and starts the turtle event loop with t.mainloop(). The complete code is provided in the article, aiming to help beginners quickly see visual results of their Python code.

import turtle as t<br/>t.speed(0)<br/>def zfx(a=200):<br/>    for i in range(4):<br/>        t.forward(a)<br/>        t.left(90)

def zfx2(a=100, x=0, y=0, c='gray', s=''):<br/>    t.up()<br/>    t.goto(x, y)<br/>    t.down()<br/>    t.fillcolor(c)<br/>    t.begin_fill()<br/>    zfx(a)<br/>    t.end_fill()<br/>    t.forward(a/2)<br/>    t.write(str(s), align='center', font=('宋体', 50, 'bold'))

def jgg(s='012345678'):<br/>    zfx2(x=-150, y=50, c='gray', s=s[0])<br/>    zfx2(x=-50, y=50, c='white', s=s[1])<br/>    zfx2(x=50, y=50, c='gray', s=s[2])<br/>    zfx2(x=-150, y=-50, c='white', s=s[3])<br/>    zfx2(x=-50, y=-50, c='gray', s=s[4])<br/>    zfx2(x=50, y=-50, c='white', s=s[5])<br/>    zfx2(x=-150, y=-150, c='gray', s=s[6])<br/>    zfx2(x=-50, y=-150, c='white', s=s[7])<br/>    zfx2(x=50, y=-150, c='gray', s=s[8])

jgg('?'*9)

import random<br/>n = [1,2,3,4,5,6,7,8,9]<br/>w = t.Screen()<br/>def run(x, y):<br/>    while True:<br/>        random.shuffle(n)<br/>        real = [(n[0]+n[1]+n[2])==15,<br/>                (n[3]+n[4]+n[5])==15,<br/>                (n[6]+n[7]+n[8])==15,<br/>                (n[0]+n[3]+n[6])==15,<br/>                (n[1]+n[4]+n[7])==15,<br/>                (n[2]+n[5]+n[8])==15,<br/>                (n[0]+n[4]+n[8])==15,<br/>                (n[2]+n[4]+n[6])==15]<br/>        if all(real):<br/>            jgg(n)<br/>            break<br/>w.onclick(run)<br/>t.mainloop()