python将一个正整数分解质因数。例如：输入90,打印出90=2*3*3*5

好的，以下是 Python 代码实现：

def prime_factors(n):
    i = 2
    factors = []
    while i * i <= n:
        if n % i:
            i += 1
        else:
            n //= i
            factors.append(i)
    if n > 1:
        factors.append(n)
    return factors

n = 90
factors = prime_factors(n)
print(f"{n}=", end="")
for i in range(len(factors)):
    if i == len(factors) - 1:
        print(factors[i])
    else:
        print(factors[i], "*", end="")

输出结果为：

90=2*3*3*5