Question

I need to make a recursive function to add positive integers inputted by a user into a list. My code works, however, I don't know how to end the loop if the user enters an exclamation mark without crashing because of conflict in type:

def listsum(numList):
theSum = 0
for i in numList:
theSum = theSum + i
return theSum


def main():
dlist=[]
add=''
while not add=="!":
add= eval(input("Enter an integer:\n"))
dlist.append(add)

print(listsum(dlist))

main()

Answer 1

eval is defining the exclamation mark as an EOF.
if you give me a moment i'll see if I can find a work around

Answer 2

eval is just making the input a number so that the sum function can work, however if the input is an exclamation mark it crashes because it is not an integer or float, I don't know how to fix that

Answer 3

def listsum(numList):
theSum = 0
for i in numList:
theSum = theSum + i
return theSum

def main():
dlist=[]
add=''
while 1:
add = input(u"Enter an integer:\n")
if add.isnumeric():
dlist.append(int(add))
elif add == "!":
break

print(listsum(dlist))

main()

Answer 4

this worked for me

Enter an integer:
5
Enter an integer:
5
Enter an integer:
5
Enter an integer:
5
Enter an integer:
5
Enter an integer:
50
Enter an integer:
!
75

Answer 5

Makes sense, Thank you very much. Just another question, how can you print a list without printing the brackets etc for example:
print(listA[::-1])
['mat', 'the', 'on', 'sat', 'dog', 'the']

Answer 6

I think you're going to need to iterate through the list and print each element instead of all elements at once.
item[0]
item[1]
ect.

Answer 7

I'm sure there is a more efficient way to do it, I will play around and let you know

Answer 8

okay

Answer 9

You just have to use a join function:

print(" ".join(string[::-1]))

Answer 10

One last thing (sorry I know you don't program in python), Python has a count function but I have to create my own, this is what I have but it keeps returning the value 6. (it is supposed to count how many times a word is repeated in the list):

def COUNT(terms,query):
counter=0
for query in terms:
counter=counter+1
print("The term {} occurs {} times".format(query,counter))

Answer 11

okay,

def COUNT(term, query):
ctr = 0
for i in range(len(term)):
if term[i] == query:
ctr += 1
print("The term {} occurs in {} times".format(query, ctr))

term = ['check', 'dog', 'red', 'check', 'orange', 'check']
COUNT(term, 'check')

that works perfectly

Answer 12

Thank you so much

Answer 13

you're welcome