1500+ Software Engineer Interview Questions and Answers for Freshers

Determine if it is possible to accommodate all passenger trips within a car's capacity without exceeding it at any point.

• Iterate through each trip and keep track of the total number of passengers in the car at each point.

• Check if the total number of passengers exceeds the car capacity at any point.

• Return 'True' if all trips can be accommodated within the car capacity, otherwise return 'False'.

The problem involves finding the number of distinct ways to climb N stairs by taking 1 or 2 steps at a time.

• Use dynamic programming to solve the problem efficiently.

• The number of ways to reach the Nth stair is the sum of the number of ways to reach the (N-1)th stair and the (N-2)th stair.

• Handle base cases for N=0 and N=1 separately.

• Consider using modulo operation to avoid overflow for large values of N.

Find the Kth largest element in an array of distinct positive integers.

• Sort the array in non-increasing order and return the Kth element.

• Ensure all elements in the array are distinct.

• Handle multiple test cases efficiently.

Perform left rotations on an array based on given queries.

• Create a function that takes the array, number of elements, number of queries, and the queries as input.

• For each query, rotate the array by the specified number of elements to the left.

• Return the final array after each rotation query.

The task is to find the Lowest Common Ancestor (LCA) of two nodes in a Binary Search Tree (BST).

• Traverse the BST from the root to find the LCA of nodes P and Q.

• Compare the values of nodes P and Q with the current node's value to determine the LCA.

• If both nodes are on the same side of the current node, move to that side; otherwise, the current node is the LCA.

• Example: For input 2 3 and BST 1 2 3 4 -1 5 6 -1 7 -1 -1 -1 -1 -1 -1, the LCA is node 1.

The task is to reverse a given string containing lowercase letters, uppercase letters, digits, and special characters.

• Iterate through the string from the last character to the first character and append each character to a new string.

• Alternatively, you can use built-in string reversal functions or methods available in your programming language.

• To solve the follow-up question with O(1) space complexity, you can use a two-pointer approach. Initialize two pointers, one at the be...read more

Yes, it is possible to get the accurate result from the given data.

• The coordinates (i,j,k) where metallic balls are present can be determined by finding the set elements in both matrix1 and matrix2.

• Additional data is not required as the given data is sufficient to determine the coordinates.

• The coordinates can be obtained by iterating through the elements of matrix1 and matrix2 and checking for set elements.

Comparing 2 basketball game scenarios with different number of trials and baskets required to win

• Calculate the probability of winning in each game scenario using binomial distribution formula

• Compare the probabilities to determine which game scenario is preferable

• In game1, the probability of winning is p. In game2, the probability of winning is the sum of probabilities of making 2 or 3 baskets

• If p is high, game1 is preferable. If p is low, game2 is preferable

• For example, if p ...read more

The task is to find the Kth largest element from a given list of numbers for each test case.

• Read the number of test cases 'T'

• For each test case, read the number of elements 'N' and the Kth largest number to find 'K'

• Sort the array in descending order and output the Kth element

Find the minimum cost to purchase a specific weight of oranges given the cost of different weight packets.

• Iterate through the list of costs and find the minimum cost to achieve the desired weight

• Keep track of the total cost while considering available packet weights

• Return -1 if it is not possible to buy exactly the desired weight

Convert decimal numbers to octal representation.

• Iterate through each test case and use built-in functions to convert decimal to octal.

• Ensure the output is in base-8 system with digits ranging from 0 to 7.

• Handle constraints such as number of test cases and range of decimal numbers.

The task is to find the length of the longest consecutive sequence in an unsorted array of integers.

• Sort the array to bring consecutive numbers together

• Iterate through the sorted array and keep track of the current consecutive sequence length

• Update the maximum length if a longer sequence is found

Return the middle node of a singly linked list, considering odd and even number of elements.

• Traverse the linked list with two pointers, one moving twice as fast as the other

• When the fast pointer reaches the end, the slow pointer will be at the middle

• Return the node pointed by the slow pointer

Reverse every alternate K nodes in a singly linked list of integers.

• Traverse the linked list in groups of K nodes and reverse every alternate group.

• Handle cases where the number of remaining nodes is less than K.

• Ensure to properly link the reversed groups to maintain the integrity of the linked list.

Generate a series of numbers by subtracting K from N until 0 or negative, then adding K back to reach N without using loops.

• Create a recursive function to generate the series.

• Subtract K from N until N is 0 or negative, then add K back until N is reached.

• Return the series as an array of integers.

The task is to identify all distinct triplets within an array that sum up to a specified number.

• Iterate through the array and use nested loops to find all possible triplets.

• Check if the sum of the triplet equals the specified number.

• Print the valid triplets or return -1 if no triplet exists.

Detect cycles in an undirected graph with given vertices and edges.

• Use Depth First Search (DFS) to traverse the graph and detect cycles.

• Maintain a visited array to keep track of visited vertices and a parent array to keep track of the parent of each vertex.

• If while traversing, you encounter a visited vertex that is not the parent of the current vertex, then a cycle exists.

• Consider edge cases like disconnected graphs and self-loops.

The task is to determine the weight of the minimum spanning tree of a given connected undirected weighted graph.

• Implement Kruskal's algorithm to find the minimum spanning tree weight.

• Sort the edges based on their weights in non-decreasing order.

• Iterate through the sorted edges and add them to the MST if they don't form a cycle.

• Keep track of the total weight of the MST and return it as the output.

Find the sum of the subarray with the maximum sum among all subarrays in an array of integers.

• Iterate through the array and keep track of the maximum sum subarray seen so far.

• At each index, decide whether to include the current element in the subarray or start a new subarray.

• Update the maximum sum subarray if a new maximum is found.

• Consider edge cases like all negative numbers in the array.

• Example: For input arr = [-2, 1, -3, 4, -1], the maximum subarray sum is 4.

Calculate total area covered by a list of rectangles on a plane.

• Iterate through each rectangle and calculate its area

• Check for overlapping areas between rectangles

• Sum up the total area covered by all rectangles

Design a stack that supports getMin() operation in O(1) time with O(1) extra space using inbuilt stack data structure.

• Use two stacks - one to store the actual data and another to store the minimum value at each level.

• When pushing a new element, check if it is smaller than the current minimum and update the minimum stack accordingly.

• When popping an element, also pop the top element from the minimum stack if it matches the popped element.

• For getMin() operation, simply return th...read more

Given a string and an integer K, create a new string by selecting the smallest character from the first K characters of the input string and repeating the process until the input string is empty.

• Iterate through the input string, selecting the smallest character from the first K characters each time.

• Remove the selected character from the input string and append it to the new string.

• Continue this process until the input string is empty.

• Return the final new string formed.

The output will be 5.

• Processor 1 initializes variable 'a' with a value of 10 and creates a pointer 'ptr' pointing to 'a'.

• Processor 1 writes the value of 'ptr' into 'file1' and then sleeps for 10 seconds.

• Processor 2 reads the contents of 'file1' and saves it in pointer 'p'.

• Processor 2 assigns the value 5 to the memory location pointed by 'p'.

• When Processor 1 wakes up and executes the printf statement, it will print the updated value of 'a', which is 5.

1. Cut cake in 8 pieces in minimum cuts. 2. Make 4 equilateral triangles using 6 matchsticks.

• 1. Cut cake in half horizontally and vertically. Cut each quarter diagonally.

• 2. Use 3 matchsticks to form a triangle. Use the other 3 to connect the centers of each triangle.

• Both puzzles require creative thinking and problem-solving skills.

Find the unique element in a sorted array where all other elements appear twice.

• Iterate through the array and XOR all elements to find the unique element.

• Use a hash set to keep track of elements and find the unique one.

• Sort the array and check adjacent elements to find the unique one.

Optimize lift usage to reduce wait times for employees entering a 10-floor building.

• Implement a smart scheduling system that prioritizes lifts based on the number of people waiting on each floor.

• Introduce a destination dispatch system where employees select their floor before entering the lift, grouping them by destination.

• Increase the number of lifts during peak hours or consider adding express lifts that service only certain floors.

• Utilize real-time data to adjust lift allo...read more

Given a string with parentheses and letters, remove minimum invalid parentheses to make it valid and return all possible valid strings.

• Use BFS to explore all possible valid strings by removing parentheses one by one

• Keep track of visited strings to avoid duplicates

• Return all unique valid strings obtained after removing minimum number of parentheses