How can I check if an element of a list that corresponds to the value of a dictionary is related to the key?

Question

Code:

entrada = ''
dici_presentes = {}
listavalores = []
while entrada != 'FIM':
    casos = int(input())
    for i in range(casos):
        nome_presente = input().split()
        c = nome_presente[0]
        v = nome_presente[1:]
        dici_presentes[c] = v
    print(dici_presentes)
    entrada = input()

Input example:

5
iara mochila estojo lapis
adelar sapato camisa carteira
jessica agenda bolsa brincos
jocelina xicara meias perfume
elaine sandalia sapatilha camiseta
iara mochila (irá retornar verdadeiro)
iara sabonete (irá retornar falso)
FIM

Exit:

Verdadeiro
Falso

Answer 1

First, the reading of the 5 entries should not be done inside the while, because you already know it will be 5 lines. The while it is only after, to read the cases in which you will verify whether the present exists or not for each person.

To read the names and the respective gifts, you can use the multiple assignment along with the unpacking:

nome, *presentes = input().split()

So if the line is, for example, iara mochila estojo lapis, the nome will be iara and presentes will be a list containing 3 elements: the strings 'mochila', 'estojo' and 'lapis'. Of course, the way you did it works too, I just wanted to show you another alternative.

Then, just keep this in the dictionary, where the nome is the key and presentes, its value:

dici_presentes = {}
casos = int(input())
for i in range(casos):
    nome, *presentes = input().split()
    dici_presentes[nome] = presentes

while True: # loop "infinito"
    entrada = input()
    if entrada == 'FIM':
        break
    else:
        nome, presente = entrada.split()
        print(presente in dici_presentes[nome])

Then I start reading the test cases. If it’s "END", I interrupt the while with break. Otherwise, I’ll do the split, taking the name and the gift. And finally, I use in to check whether the presente is on the list corresponding to nome.

The code above prints True and False, but if you want to change the text, just do:

while True:
    entrada = input()
    if entrada == 'FIM':
        break
    else:
        nome, presente = entrada.split()
        if presente in dici_presentes[nome]:
            print('Verdadeiro')
        else:
            print('Falso')

---

One detail is that the above code does not check if the name really is a dictionary key (it always assumes it is). If you have to check these cases too, just change the condition to:

if nome in dici_presentes and presente in dici_presentes[nome]:
    print('Verdadeiro')
else:
    print('Falso')

I mean, first I see if nome is a key, and only then see if the presente is on its list.

Another way is:

if presente in dici_presentes.get(nome, []):
    print('Verdadeiro')
else:
    print('Falso')

The get tries to get the value of the key specified by nome, and if not found, returns [] (an empty list). That is, if the nome is not a dictionary key, the presente will not be found, since the empty list has no element and therefore no presente will be in it.