mirror of
https://github.com/krahets/hello-algo.git
synced 2024-12-26 13:06:28 +08:00
1c0f350ad6
* Add the intial translation of code of all the languages * test * revert * Remove * Add Python and Java code for EN version
53 lines
1.3 KiB
Python
53 lines
1.3 KiB
Python
"""
|
|
File: hanota.py
|
|
Created Time: 2023-07-16
|
|
Author: krahets (krahets@163.com)
|
|
"""
|
|
|
|
|
|
def move(src: list[int], tar: list[int]):
|
|
"""Move a disc"""
|
|
# Take out a disc from the top of src
|
|
pan = src.pop()
|
|
# Place the disc on top of tar
|
|
tar.append(pan)
|
|
|
|
|
|
def dfs(i: int, src: list[int], buf: list[int], tar: list[int]):
|
|
"""Solve the Tower of Hanoi problem f(i)"""
|
|
# If only one disc remains on src, move it to tar
|
|
if i == 1:
|
|
move(src, tar)
|
|
return
|
|
# Subproblem f(i-1): move the top i-1 discs from src with the help of tar to buf
|
|
dfs(i - 1, src, tar, buf)
|
|
# Subproblem f(1): move the remaining one disc from src to tar
|
|
move(src, tar)
|
|
# Subproblem f(i-1): move the top i-1 discs from buf with the help of src to tar
|
|
dfs(i - 1, buf, src, tar)
|
|
|
|
|
|
def solve_hanota(A: list[int], B: list[int], C: list[int]):
|
|
"""Solve the Tower of Hanoi problem"""
|
|
n = len(A)
|
|
# Move the top n discs from A with the help of B to C
|
|
dfs(n, A, B, C)
|
|
|
|
|
|
"""Driver Code"""
|
|
if __name__ == "__main__":
|
|
# The tail of the list is the top of the pillar
|
|
A = [5, 4, 3, 2, 1]
|
|
B = []
|
|
C = []
|
|
print("Initial state:")
|
|
print(f"A = {A}")
|
|
print(f"B = {B}")
|
|
print(f"C = {C}")
|
|
|
|
solve_hanota(A, B, C)
|
|
|
|
print("After the discs are moved:")
|
|
print(f"A = {A}")
|
|
print(f"B = {B}")
|
|
print(f"C = {C}")
|