10+ Dana India Interview Questions and Answers

The task is to determine if a given singly linked list forms a cycle or not.

• A cycle occurs when a node's next points back to a previous node in the list.

• To solve this problem, we can use the Floyd's Cycle-Finding Algorithm.

• The algorithm uses two pointers, one moving at a normal pace and the other moving twice as fast.

• If there is a cycle, the fast pointer will eventually catch up to the slow pointer.

• If the fast pointer reaches the end of the list (i.e., it encounters a null no...read more

The problem is to find the intersection of two sorted arrays.

• Use two pointers to iterate through the arrays.

• Compare the elements at the current pointers and move the pointers accordingly.

• If the elements are equal, add it to the intersection array and move both pointers.

• If the element in the first array is smaller, move the first pointer.

• If the element in the second array is smaller, move the second pointer.

• Repeat until one of the pointers reaches the end of its array.

• Return t...read more

The minimum depth of a binary tree is the number of nodes along the shortest path from the root node down to the nearest leaf node.

• The minimum depth can be found by performing a breadth-first search (BFS) traversal of the binary tree

• During the BFS traversal, keep track of the current level and increment the depth by 1 for each level

• Stop the BFS traversal when a leaf node is encountered and return the depth as the minimum depth of the binary tree

Segmentation fault occurs when a program tries to access memory it doesn't have permission to access.

• Segmentation fault occurs when a program tries to access memory outside of its allocated space.

• Compiler detects segmentation faults by checking memory access permissions during compilation.

• Segmentation faults are typically caused by dereferencing a null pointer or accessing an out-of-bounds array element.

A mutex is a binary semaphore used for mutual exclusion, while a semaphore is a generalized synchronization primitive.

• Mutex is used to protect a critical section of code, allowing only one thread to access it at a time.

• Semaphore is used to control access to a shared resource, allowing multiple threads to access it simultaneously.

• Mutex has ownership, meaning the thread that locks it must unlock it.

• Semaphore does not have ownership, meaning any thread can release it.

• Mutex is ty...read more

Global variables are accessible throughout the program, while static variables are limited to the scope in which they are defined.

• Global variables are declared outside of any function and can be accessed by any function in the program.

• Static variables are declared within a function and retain their value between function calls.

• Example: int globalVar = 10; static int staticVar = 5;

• Example: Global variable can be accessed in multiple functions, while static variable retains its...read more

To get the right and left view of a binary tree, perform a level order traversal and keep track of the first node encountered at each level.

• Perform a level order traversal of the binary tree

• Keep track of the first node encountered at each level for both left and right views

• Store the first node encountered at each level in separate arrays for left and right views

Calculate average, top 10 and bottom 10 elements of a given stream of integers.

• Create a variable to store the sum of integers and another variable to store the count of integers.

• Use a loop to read the integers from the stream and update the sum and count variables.

• Calculate the average by dividing the sum by the count.

• Sort the integers in ascending order and print the first 10 elements for bottom 10.

• Sort the integers in descending order and print the first 10 elements for top...read more

Processes are independent instances of a program, while threads are smaller units within a process sharing resources.

• Processes have their own memory space, while threads share the same memory space within a process.

• Processes are heavyweight, requiring more resources, while threads are lightweight.

• Processes communicate with each other through inter-process communication mechanisms, while threads can communicate directly through shared memory.

• Example: A web browser running mult...read more

Use Floyd's Tortoise and Hare algorithm to detect cycle in a linked list.

• Initialize two pointers, slow and fast, at the head of the linked list.

• Move slow pointer by one step and fast pointer by two steps.

• If they meet at some point, there is a cycle in the linked list.