b.limour.top/source/_posts/random-choice.md

---

title: random.choice tags:

• Python
• random.choice id: '129' categories:

• • Python练习

    date: 2020-05-30 15:30:50

    from decimal import Decimal
    import random, re
    
    rd = re.compile(r'^-?\d*(?:\.\d*)?\d$')
    Norm = Decimal('0.01')
    
    def randint(a=0, b=10):
    return str(random.randint(a,b))
    
    def _add():
    a, b = randint(), randint()
    return f'{a} + {b} =', Decimal(a) + Decimal(b)
    
    def _sub():
    a, b = randint(), randint()
    return f'{a} - {b} =', Decimal(a) - Decimal(b)
    
    def _mul():
    a, b = randint(), randint()
    return f'{a} * {b} =', Decimal(a) * Decimal(b)
    
    def _dev():
    a, b = randint(), randint(1)
    return f'{a} / {b} =', (Decimal(a) / Decimal(b)).quantize(Norm, rounding = 'ROUND_HALF_UP')
    
    opset = (_add, _sub, _mul, _dev)
    def _op():
    return random.choice(opset)()
    
    total = correct = 0
    al = []
    ct = ''
    while True:
    if ct != 'y':
    expression, answer = _op()
    else:
    ct = ''
    ua = input(f'第{total+1}题:  {expression} ').replace(' ','')
    if rd.match(ua):
    total += 1
    if Decimal(ua).quantize(Norm, rounding = 'ROUND_HALF_UP') == answer:
        correct += 1
        al.append(f'第{total}题: {expression} {ua} 正确！')
        #print("此题回答正确！" )
    else:
        al.append(f'第{total}题: {expression} {ua} 错误！标准答案是 {answer}')
        #print(f"此题回答错误！标准答案是 {answer}" )
    else:
    while True:
        ct = input('输入错误，是否继续(y/n)').strip().lower()
        if ct in 'yn':
            break
    if ct == 'n':
        break