"""第 25 课补全练习：检查三份材料是否串卷。修改 solve，保持下方检查不变。"""
import math, io, argparse
import torch
from torch import nn
from torch.nn import functional as F
torch.set_num_threads(2)
torch.manual_seed(26)

def solve(train, val, test):
    return not (train & val or train & test or val & test)

assert solve({'a'},{'b'},{'c'})
assert not solve({'a'},{'a'},{'c'})
print("本课补全练习通过。")