在collat​​z序列之后的总计步骤？

Question

我不确定如何使用此代码获取collat​​z序列中的步骤总数：

number = int(input('Enter a number, please:'))  

while number > 1:  
    if number % 2 == 0:  
        number = number / 2  
        print(number)  
    else:  
        number = number * 3 + 1  
        print(number)  
    # print('Steps required:',NEED TO FILL , end='')  

Answer 1

您似乎只想计算while循环内所采取的步骤。添加count变量并打印结果如下所示：

number = int(input('Enter a number, please:'))

#initiate step count
steps = 0
while number > 1:
    if number % 2 == 0:
        number = number / 2
        print(number)
    else:
        number = number * 3 + 1
        print(number)
    # add a step for each loop
    steps += 1
print('Steps required: {}'.format(steps))

在shell中运行它会产生：

$ python3 -i collatz.py 
Enter a number, please:14
7.0
22.0
11.0
34.0
17.0
52.0
26.0
13.0
40.0
20.0
10.0
5.0
16.0
8.0
4.0
2.0
1.0
Steps required: 17

Answer 2

试试这个：

def collatz(number):

    if(number%2==0):
        n=number//2
        print(n,"\t",end="")
        return n
    else:
        ev=3*number+1
        print(ev,"\t",end="")
        return ev

num1=input("Enter a number: \n")
step=0
try:
    num=int(num1)

    if(num==1):
        print("Enter an integer greater than 1")
    elif(num>1):
        a=collatz(num) 
        while(True):
            if(a==1):
                step=step+1
                break
            else:
                a=collatz(a)
                step+=1
        print("\nNumber of steps needed:",step)

    else:
        print("Please, Enter a positive integer to begin the Collatz sequence")


except:
    print("please, Enter an integer")