Vrftsjtryk

I'm new to programming and currently taking a CSC 110 class. Our assignment is to create a bunch functions that do all sorts of things with some data that is given. I have taken all that data and put it into a dictionary but I'm having some trouble getting the data I want out of it.

Here is my problem:

I have a dictionary that stores a bunch of countries followed by a list that includes their population and GDP. Formatted something like this

{'country': [population, GDP], ...}

My task is to loop through this and find the country with the highest population or GDP then print:

'The country with the highest population is ' + highCountry+

    ' with a population of ' + format(highPop, ',.0f')+'.')

In order to do this I wrote this function (this one is specifically for highest population but they all look about the same).

def highestPop(worldInfo):

        highPop = worldInfo[next(iter(worldInfo))][0] #Grabs first countries Population

        highCountry = next(iter(worldInfo))#Grabs first country in worldInfo



        for k,v in worldInfo.items():

                if v[0] > highPop:

                    highPop = v[0]

                    highCountry = k



        return highPop,highCountry

While this is working for me I gotta think there is an easier way to do this. Also I'm not 100% sure how [next(iter(worldInfo))] works. Does this just grab the first value it sees?

Thanks for your help in advance!

Edit: Sorry I guess I wasn't clear. I need to pass the countries population but also the countries name. So I can print both of them in my main function.

I think you're looking for this:

max(worldInfo.items(), key=lambda x: x[1][0])

This will return both the country name and its info. For instance:

('france', [100, 22])

The next() and iter() functions are for python iterators. For example:

mytuple = ("apple", "banana", "cherry")

myit = iter(mytuple)



print(next(myit)) #=> apple

print(next(myit)) #=> banana

print(next(myit)) #=> cherry

Use the max() function, like so:

max(item[0] for item in county_dict.values()) #use item[1] for GDP!

Also try storing the values not in a list ([a, b]) but in a tuple ((a, b)).

Edit: Like iamanigeeit said in the comments, this works to give you the country name as well:

max(data[0], country for country, data in country_dict.items())

An efficient solution to get the key with the highest value: you can use the max function this way:

highCountry = max(worldInfo, key=lambda k: worldInfo[k][0])

The key argument is a function that specifies what values you want to use to determine the max.max(data[0], country for country, data in country_dict.items())

And obviously :

highPop = worldInfo[highCountry][0]