I just started learning Python and am stuck with an exercise.
The program should ask the user for a number and then print out a list including all of the number's divisors.
myList = []
usernumber = int(input("Please enter a number: "))
a = int(1)
for a in range(1, usernumber):
while usernumber % a == 0:
divisor = usernumber / a
myList.append(divisor)
a += 1
print(*myList)
This seems to work for everything except 1, but I can't figure out what I have to change to make it work for an input of 1. Any ideas?
Try this:
myList = []
usernumber = int(input("Please enter a number: "))
#No need to declare a as an integer, for loop does that for you.
for a in range(1, usernumber+1):
#usernumber+1 as range() does not include upper bound.
#For each number leading up to the inputted number, if the
#remainder of division is 0, then add to myList.
if usernumber % a == 0:
myList.append(a)
print(myList)
Related
I'm starting next month full stack developer and im doing some practicing
i started with Python and i want to make some code
with while loop that will ask the user to input how many integers they want
and i want to calculate all the numbers
im doing something wrong not sure what
thanks in advance
oz
example:
number = int(input('Enter how many integer: '))
my_list = [number]
while len(my_list) < number:
user_input = int(input('Enter a integer: '))
my_list.append(user_input)
print(user_input+number)
print(my_list)
number = int(input('Enter how many integer: '))
my_list = []
while len(my_list) < number:
user_input = int(input('Enter a integer: '))
my_list.append(user_input)
print(user_input, ' ' ,number)
print(my_list)
Fellow python developers. I have a task which I can't seem to crack and my tutor is MIA. I need to write a program which only makes use of while loops, if, elif and else statements to:
Constantly ask the user to enter any random positive integer using int(raw_input())
Once the user enters -1 the program needs to end
the program must then calculate the average of the numbers the user has entered (excluding the -1) and print it out.
this what I have so far:
num = -1
counter = 1
anyNumber = int(raw_input("Enter any number: "))
while anyNumber > num:
anyNumber = int(raw_input("Enter another number: "))
counter += anyNumber
answer = counter + anyNumber
print answer
print "Good bye!"
Try the following and ask any question you might have
counter = 0
total = 0
number = int(raw_input("Enter any number: "))
while number != -1:
counter += 1
total += number
number = int(raw_input("Enter another number: "))
if counter == 0:
counter = 1 # Prevent division by zero
print total / counter
You need to add calculating average at the end of your code.
To do that, have a count for how many times the while loop runs, and divide the answer at the end by that value.
Also, your code is adding one to the answer each time because of the line - answer = counter + anyNumber, which will not result in the correct average. And you are missing storing the first input number, because the code continuously takes two inputs. Here is a fixed version:
num = -1
counter = 0
answer = 0
anyNumber = int(raw_input("Enter any number: "))
while anyNumber > num:
counter += 1
answer += anyNumber
anyNumber = int(raw_input("Enter another number: "))
if (counter==0): print answer #in case the first number entered was -1
else:
print answer/counter #print average
print "Good bye!"
There's another issue I think:
anyNumber = int(raw_input("Enter any number: "))
while anyNumber > num:
anyNumber = int(raw_input("Enter another number: "))
The value of the variable anyNumber is updated before the loop and at the beginning of the loop, which means that the first value you're going to enter is never going to be taken in consideration in the average.
A different solution, using a bit more functions, but more secure.
import numpy as np
numbers = []
while True:
# try and except to avoid errors when the input is not an integer.
# Replace int by float if you want to take into account float numbers
try:
user_input = int(input("Enter any number: "))
# Condition to get out of the while loop
if user_input == -1:
break
numbers.append(user_input)
print (np.mean(numbers))
except:
print ("Enter a number.")
You don't need to save total because if the number really big you can have an overflow. Working only with avg should be enough:
STOP_NUMBER = -1
new_number = int(raw_input("Enter any number: "))
count = 1
avg = 0
while new_number != STOP_NUMBER:
avg *= (count-1)/count
avg += new_number/count
new_number = int(raw_input("Enter any number: "))
count += 1
I would suggest following.
counter = input_sum = input_value = 0
while input_value != -1:
counter += 1
input_sum += input_value
input_value = int(raw_input("Enter any number: "))
try:
print(input_sum/counter)
except ZeroDivisionError:
print(0)
You can avoid using two raw_input and use everything inside the while loop.
There is another way of doing..
nums = []
while True:
num = int(raw_input("Enter a positive number or to quit enter -1: "))
if num == -1:
if len(nums) > 0:
print "Avg of {} is {}".format(nums,sum(nums)/len(nums))
break
elif num < -1:
continue
else:
nums.append(num)
Here's my own take on what you're trying to do, although the solution provided by #nj2237 is also perfectly fine.
# Initialization
sum = 0
counter = 0
stop = False
# Process loop
while (not stop):
inputValue = int(raw_input("Enter a number: "))
if (inputValue == -1):
stop = True
else:
sum += inputValue
counter += 1 # counter++ doesn't work in python
# Output calculation and display
if (counter != 0):
mean = sum / counter
print("Mean value is " + str(mean))
print("kthxbye")
I find my prog's if-else does not loop, why does this happen and how can I fix it for checking?
my prog supposed that store user's inputs which must between 10 and 100, then delete duplicated inputs.
examples: num=[11,11,22,33,44,55,66,77,88,99]
result: `[22,33,44,55,66,77,88,99]
inList=[]
for x in range(1,11):
num = int(input("Please enter number "+str(x)+" [10 - 100]: "))
if num >= 10 and num <= 100:
inList.append(num)
else:
num = int(input("Please enter a valid number: "))
print(inList)
I found that the if-else only did once, so when I enter invalid num for the 2nd time, the prog still brings me to the next input procedure. What happen occurs?
Please enter number 1 [10 - 100]: 1
Please enter a valid number: 1
Please enter number 2 [10 - 100]:
Additionally, may I ask how can I check the inList for duplicated num, and then remove both of the num in the list?
I'd also suggest a while loop. However the while loop should only be entered if the first prompt is erraneous:
Consider this example:
inList = []
for x in range(1,11):
num = int(input("Please enter number "+str(x)+" [10 - 100]: "))
while not (num >= 10 and num <= 100):
num = int(input("Please enter a valid number [10 - 100]: "))
inList.append(num)
print(inList)
However, may I suggest something else:
This code creates a list of valid inputs ["10","11"...."100"] and if the input which by default is a string is not inside that list we ask for new input. Lastly we return the int of that string. This way we make sure typing "ashashah" doesn't throw an error. Try it out:
inList = []
valid = list(map(str,range(10,101)))
for x in range(1,11):
num = input("Please enter number {} [10 - 100]: ".format(x))
while num not in valid:
num = input("Please enter a valid number [10 - 100]: ")
inList.append(int(num))
print(inList)
I'm no python expert, and I don't have an environment setup to test this, but I can see where your problem comes from.
Basically, inside your for loop you are saying
if num is valid then
add to array
else
prompt user for num
end loop
There's nothing happening with that second prompt, it's just prompt > end loop. You need to use another loop inside your for loop to get num and make sure it's valid. The following code is a stab at what should work, but as said above, not an expert and no test environment so it may have syntax errors.
for x in range(1,11):
i = int(0)
num = int(0)
while num < 10 or num > 100:
if i == 0:
num = int(input("Please enter number "+str(x)+" [10 - 100]: "))
else:
num = int(input("Please enter a valid number: "))
i += 1
inList.append(num)
print(inList)
I have been asked to make a piece of code including a for loop and a while loop. I was asked to:
Get the user to input a number
Output the times table for that number
Starts again every time it finishes
I was able to do the for loop like so:
num= int(input ("Please enter a number."))
for x in range (1,13):
print (num,"x",x,"=",num*x)
But I cannot figure out how to make it repeat, any ideas?
Just put your code inside a while loop.
while True:
num = int(input("Please enter a number: "))
for x in range(1,13):
print("{} x {} = {}".format(num, x, num*x))
I think it would be nice for you to handle errors.
If a user decides to enter a non digit character it will throw an error.
while True:
num = input('please enter a number')
if num ==0:
break
elif not num.isdigit():
print('please enter a digit')
else:
for x in range(1, 13):
mult = int(num)
print('%d x %d = %d' %(mult, x, mult*x))
I'm writing for creating a list of number from input and get the average of the list. The requirement is: when the user enters a number, the number will be appended to the list; when the user press Enter, the input section will stop and conduct and calculation section.
Here is my code:
n = (input("please input a number"))
numlist = []
while n != '':
numlist.append(float(n))
n = float(input("please input a number"))
N = 0
Sum = 0
for c in numlist:
N = N+1
Sum = Sum+c
Ave = Sum/N
print("there are",N,"numbers","the average is",Ave)
if I enter numbers, everything works fine. But when I press Enter, it shows ValueError. I know the problem is with float(). How can I solve this?
You don't need the float() around the input() function inside your loop because you call float() when you append n to numlist.
this should solve ur prob ,by adding a try,catch block around ur print statement
n = (input("please input a number"))
numlist = []
while True :
numlist.append(float(n))
#####cath the exception and break out of
try :
n = float(input("please input a number"))
except ValueError :
break
N = 0
Sum = 0
for c in numlist:
N = N+1
Sum = Sum+c
Ave = Sum/N
print("there are",N,"numbers","the average is",Ave)