challenges | A repository for challenges for various tech stacks

I am building an app following the Rest Countries API challenge from frontendmentor. I have run into a problem. When trying to find the border countries full name using the alpha3code, I get the error : TypeError: Cannot read property 'name' of undefined.

I am solving this problem on dynamic array in which input first line contains two space-separated integers,n, the size of arr to create, and q, the number of queries, respectively. Each of the q subsequent lines contains a query string,queries[i]. it expects to return int[]: the results of each type 2 query in the order they are presented.

i tried to attempt as below and my code seems fine to me but it gives segmentation fault error. please help me where I am getting conceptually wrong. thanks.

problem: Declare a 2-dimensional array,arr , of n empty arrays. All arrays are zero indexed. Declare an integer,last answer , and initialize it to zero.

There are 2 types of queries, given as an array of strings for you to parse:

Query: 1 x y

Let idx=((queries[i][1]^last_answer)%n);. Append the integer y to arr[idx].

Query: 2 x y

Let idx=((queries[i][1]^last_answer)%n);. Assign last_answer=arr[idx][queries[i][2]%(arr[idx].size())] . Store the new value of last_answer to an answers array.

input: 2 5

1 0 5

1 1 7

1 0 3

2 1 0

2 1 1

output:

7

3

I am trying an exercise that requires you to:

write a program that returns a list that contains only the elements that are common between the lists (without duplicates). Make sure your program works on two lists of different sizes.

I was able to do this, but one of the extra challenges is to:

Write this in one line of Python

I came up with the following code:

I've begun learning Go, and I ran into a strange bug, and an even stranger fix for it working on a HackerRack problem:

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Let's say that you have a string:

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On my current website I initialize this plugin as follow:

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According to Hadley's Advanced R, packages attached by library() and require() become parents of the global environment. This implies, however, that if I attach a package inside my toy REPL it will become the parent of the global environment even I'm not running it on the global environment.

For example (please note that the R> prompt is the "normal" R terminal, and that >>>> is my REPL's "terminal"):

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Input data: