Arista Network Interview | Set 1

Round 1 : Technical Interview

Question 1: Given a sorted doubly link list and two numbers C and K. You need to decrease the info of node with data K by C and insert the new node formed at its correct position such that the list remains sorted.
Complete working code with test cases was required .

Question 2: Given a binary tree , and two values a and b, find the shortest length between the nodes with info a and b.

Question 3: Basics of synchronization , test and set, locks, mutex. (wrote a code and kept on adding constraints ,asked if code would work in mutiprocessor, uniprocessor, multithreaded system).

Round 2 : C/C++ concepts + HR
The round began with detailed description of projects. Then, He went into the details of printf function, format string and variable arguments and asked to implement my own printf function.
Interviewer wrote basic C programs on shared screen and output had to be predicted.

          Eg. 1 )
          int main(int argc , char *argv[])
           {
               printf("%c",**++argv);
           }

           Eg. 2)

          int *x[N];
          x=(int(*)[N])malloc(M*sizeof(*x));
          printf("%d %d",sizeof(x),sizeof(*x));

          Eg 3) Asked significance of return statement in C. 
                What does '0' in return(0) means.

          Eg 4) Some questions based on pointing out errors in program 
               (eg. modifying read only string , concepts of constant 
                pointer to string )

          Eg 5) 10000 students are there and each student has one bit 
                data. how can you     modify his data in O(1) time .

          Eg 6 ) Structure Padding details .

          Eg 7) https://www.geeksforgeeks.org/struct-hack/

Basic HR questions

Round 3 : Technical Interview

Question 1 : Given a large file which contains m rows and n columns. Given a column no, sort the column in such a way that corresponding rows also sorted.

Question 2 : Suggest a way to search in sorted link list in better then O(n) time . ( Skip lists )

Question 3 : LRU cache implementation.

Question 4 : Find the mean and median of the elements such that elements are dynamically added at runtime( only approach).

Finally, Why do you want to join Arista networks.