What to learn before you start programming

• Should be good in logical thinking, Understanding the terms.

• Should know concepts of variables, methods, looping structures.

• Should have little knowledge on Data Structures.

Programming Questions for Beginner's

Questions on Strings :

Question 1 : How to reverse a String in java? Can you write a program without using any java inbuilt methods?

Question 2 : Write a java program to check if two Strings are anagram in java?

Question 3 : Write a program to check if String has all unique characters in java?

Question 4 : How to check if one String is rotation of another String in java?

Question 5 : How to find duplicate characters in String in java? Question 6 : Find first non repeated character in String in java?

Question 7 : Find all substrings of String in java?

Question 8 : Find length of String without using any inbuilt method in java?

Question 9 : Write a program to print all permutations of String in java?

Questions on Arrays :

Question 10 : Write java Program to Find Smallest and Largest Element in an Array.

Question 11 : Find missing number in the array.

Question 12 : Search an element in rotated and sorted array.

Question 13 : Find minimum element in a sorted and rotated array.

Question 14: Find second largest number in an array.

Question 15 : Find the number occurring odd number of times in an array.

Question 16 : Find minimum number of platforms required for railway station.

Question 17 : Find a Pair Whose Sum is Closest to zero in Array.

Question 18 : Given a sorted array and a number x, find the pair in array whose sum is closest to x.

Question 19 : Find all pairs of elements from an array whose sum is equal to given number.

Question 20: Given an array of 0’s and 1’s in random order, you need to separate 0’s and 1’s in an array.

Question 21 : Separate odd and even numbers in an array.

Question 22 : Given an array containing zeroes, ones and twos only. Write a function to sort the given array in O(n) time complexity.

Question 23 : Find local minima in array.

Question 24 : Sliding window maximum in java.

Question 25 : Count number of occurrences (or frequency) of each element in a sorted array.

Question 26 : Find subarrays with given sum in an array.

Question 27 : Find peak element in the array.

Question 28 : Find leaders in an array.

Question 29 : Count 1’s in sorted Binary Array.

Question 30 : Find first repeating element in an array of integers.

Question 31 : Check if Array Elements are Consecutive.

Question 32 : Permutations of array in java.

Question 33 : Rotate an array by K positions.

Question 34 : Stock Buy Sell to Maximize Profit.

Question 35 : Find maximum difference between two elements such that larger element appears after the smaller number.

Question 36 : Search in a row wise and column wise sorted matrix.

Question 37 : Largest sum contiguous subarray.

Question 38 : Find the Contiguous Subarray with Sum to a Given Value in an array.

Question 39 : Longest Common Prefix in an array of Strings in java.

Question 40 : Find all subsets of set (power set) in java.

Questions on Stack :

Question 41: Implement a stack using array.

Question 42: Implement a stack using Linked List.

Question 43: Implement a stack using two queues.

Question 44 : Sort an stack using another stack Queue.

Question 45: Implement Queue using Array in java.

Question 46: Implement a stack using two queues .

Questions on LinkedList :

Question 47 : Implement singly linked list in java.

Question 48: How to reverse linked list in java.

Question 49: How to find middle element of linked list.

Question 50 : How to find nth element from end of linked list .

Question 51 : How to detect a loop in linked list. If linked list has loop, find the start node for the loop.

Question 52: How to check if linked list is palindrome or not?

Question 53 : Find intersection of two linked lists?

Question 54 : How to reverse a linked list in pairs?

Question 55 : Implement Doubly linked list in java? Binary Tree?

Question 56 : How can you traverse binary tree?

Question 57 : Write an algorithm to do level order traversal of binary tree?

Question 58 : Write an algorithm to do spiral order traversal of binary tree?

Question 59 : How can you print leaf nodes of binary tree?

Question 60 : How to count leaf nodes of binary tree.

Question 61 : How to print all paths from root to leaf in binary tree.

Question 62 : How to find level of node in binary tree.

Question 63 : How to find maximum element in binary tree.

Question 64 : How to find lowest common ancestor(LCA) in binary tree.

Question 65 : How to do boundary traversal of binary tree.

Question 66 : How to print vertical sum of binary tree?

Question 67 : Count subtrees with Sum equal to target in binary tree?

Questions on Binary Search :

Question 68 : What is binary search tree?

Question 69 : Can you write algorithm to insert a node in binary search tree.

Question 70 : Can you write algorithm to delete a node in binary search tree.

Question 71 : How can you find minimum and maximum elements in binary search tree?

Question 72 : How to find lowest common ancestor(LCA) in binary search tree.

Question 73 : Find in order successor in a Binary search Tree.

Question 74 : Convert sorted array to balanced BST

Question 75 : Convert sorted Linked List to balanced BST

Question 76 : Check if a binary tree is binary search tree or not in java Sorting

Question 77 : Write an algorithm to implement bubble sort?

Question 78 : Write an algorithm to implement insertion sort sort?

Question 79 : Write an algorithm to implement selection sort sort?

Question 80 : Can you write algorithm for merge sort and also do you know complexity of merge sort?

Question 81 : Do you know how to implement Heap sort?

Question 82 : Implement quick sort in java?

Question 83 : Implement shell sort in java?

Question 84 : Implement Counting sort in java?

Question 85 : What is binary search? Can you write an algorithm to find an element in sorted array using binary search?

Questions on Graph :

Question 86 : Write algorithm to do depth first search in a graph.

Question 87 : Write algorithm to do breadth first search in a graph.

Question 88 : Explain Dijkstra algorithm from source to all other vertices.

Question 89 : Explain Bellman Ford algorithm to find shortest distance

Question 90 : Explain Kruskal’s algorithm for finding minimum spanning tree Dynamic Programming

Question 91 : Given two String, find longest common substring.

Question 92 : Given two Strings A and B. Find the length of the Longest Common Subsequence (LCS) of the given Strings.

Question 93 : Given a matrix, we need to count all paths from top left to bottom right of MxN matrix. You can either move down or right.

Question 94 : Edit Distance Problem in java.

Question 95: Coin change problem in java Question 96 : Minimum number of jumps to reach last index