编程将一个正整数分解成质因数例如: 输入 90 输出 90=2*3*3*5

编程将一个正整数分解成质因数的过程可以通过循环和判断来实现。以下是一个示例代码：

def prime_factors(n):
    factors = []
    i = 2
    while i <= n:
        if n % i == 0:
            factors.append(i)
            n = n / i
        else:
            i += 1
    return factors

def format_factors(n, factors):
    result = str(n) + " = "
    for i in range(len(factors)):
        result += str(factors[i])
        if i != len(factors) - 1:
            result += " * "
    return result

def decompose_integer(n):
    factors = prime_factors(n)
    result = format_factors(n, factors)
    return result

number = int(input("请输入一个正整数："))
result = decompose_integer(number)
print(result)

运行以上代码，输入一个正整数，程序将会输出该正整数的质因数分解结果。