Python def function assignment issue-CodePudding

I was given an assignment in which I was supposed to make program which does different kind of calculations/ functions by giving the number of the function (must use function with def). And got seriously stuck with it.

choice = int(input("Chosen function: "))
while choice != 0
if choice == 1:
    print("Sum of the list: ", summ_list(lista))
if choice == 2:
    print("Is the chosen number inside?: ", decide_if_in(lista, s))
.......
else:
    print("The program closes.")

If the user presses 0 the program should terminate. However to all my best effort if I make a while or for loop it will get stuck in an infinite loop thus I am unable to solve it.

def decide_if_in():
    s = int(input("Which number do you think is in the list?: "))
    for d in s:
        if d == s:
             print("It is in the list")
        else:
            print("It is not in the list..")

Here it does work without the def tag but I cant make it work with it. The point would be I give it a number and it checks the list that is it inside the list?

CodePudding user response：

In your example 1, you are not updating choice inside your loop. That is why it is stuck in infinite loop. You can write it as,

choice = int(input("Chosen function: "))
while choice != 0:
    if choice == 1:
        print("Sum of the list: ", summ_list(lista))
        choice = int(input("Chosen function: "))
    if choice == 2:
        print("Is the chosen number inside?: ", decide_if_in(lista, s))
        choice = int(input("Chosen function: "))
.......
    else:
        print("The program closes.")

A tiny bit of tip- in python, you can directly put functions in list or dictionary. So, you can do something like

def func1(arg1):
    #do something here
def func2(arg1):
    #do something else

func_dic = {1:func1, 2:func2}
choice = int(input("Whatever: "))
while choice != 0:
    print("Whatever: ", func_dic[choice](list))
                        ^^^^^^^^^^^^^^^^ -> function of choice here
print("close dialogue")

For your second code, your definition is wrong. You can simply do it by

def func_name(lista):
    s = int(input("Whatev: "))
    if s in lista:
        return "It's in"
    else:
        return "It's not in"

CodePudding user response：

choice = int(input("Chosen function: "))
while 1: # Loops infinitely, using exit() to stop the script
    if choice == 1:
        print("Sum of the list: ", summ_list(lista))
    elif choice == 2: # Better to use elif
        print("Is the chosen number inside?: ", decide_if_in(lista))
    .....
    elif choice == 0:
        print("The program closes.")
        exit() # Stops the python script
    choice = int(input("Chosen function: ")) # Asking for input again

def decide_if_in(lista): # Taking the list as an arg
    s = int(input("Which number do you think is in the list?: "))
    if s in list:
        print("It is in the list")
    else:
        print("It is not in the list..")