We are given an array of elements. We need to find whether the elements in the array are in Geometric Progression (GP) or not after removing any 1 element from the array. We can run out the possibilities and with observations to figure out that the first element is fake, or the second element is fake, or these 2 elements will give the common ratio of the array. After the common ratio is found, we can iterate on the array to see if all elements follow that rule. 2 base conditions would be to check if the first and second ... Read More

The problem involves removing elements from any side of a list of integers in such a way that 2*min is greater than max. vector arr = {250, 10, 11, 12, 19, 200}; res = solve(arr); We can use brute force approach. We can try all possible subarrays which satisfy and find the longest one in which 2*min > max condition holds. We can also use dynamic programming approach to try all possible subarray combinations that are overkill and not required. Example  (Using Vector ADT) Suppose we have an array such as “[250, 10, 11, 12, 19, 200]”. To get ... Read More

A linked list is a sequence of elements that are connected together. Each list have a head and series of nodes and each node has data of the current node and link to next node. The basic operations of a linked list are insertion, deletion, search and delete. Removing duplicates from a sorted linked list One way to remove nodes from is using recursion. The idea is to compare each node with its adjacent node and delete the duplicate one they are equal. Our recursive call will return us to the next node. So for the next element, we will ... Read More

Given a number in the form of a string, we need to find where to make it divisible by eight after deleting zero or more elements. In other words, we need to find whether there is a subsequence of the string, which is divisible by 8. Return the modified string or -1 if it is not possible. According to divisibility rules, any number whose last three digits are divisible by 8 is also divisible by 8. For example, 56992992 and 476360 are divisible by 8, but 2587788 is not. If the result is a whole number, then the original number ... Read More

Given an algebraic string like p-(q-r)-s, we need to remove the brackets and convert this string to a string with the same mathematical result. So the string p-(q-r)-s is converted to p-q+r-s, giving us the same mathematical result. To achieve this, we can use a stack and keep track of whether or not we should flip the upcoming signs in the bracket expression. 0 mean + or no flip 1 mean - or flip So on every bracket opening, we will push either 0 or 1 depending on whether the signs in this bracket will flip or not. ... Read More

In this problem, we have a binary tree with a path from the root node to the leaf node that is completely defined. The sum of all nodes from the root node to the leaf node must be greater than or equal to, a constant value, k. So we need to remove all nodes in those paths whose sum is less than k, such that the only paths left in the tree will be greater than k. An important thing to remember here is that a node may be a part of many paths, so only remove such nodes if ... Read More

Given a number in the form of a string, we need to find where to make it divisible by eight after deleting zero or more elements. In other words, we need to find whether there is a subsequence of the string, which is divisible by 8. Return the modified string or -1 if it is not possible.Any number whose last three digits are divisible by 8 is also divisible by 8. For example, 56992992 and 476360 are divisible by 8, but 2587788 is not. If the result is a whole number, then the original number is divisible by 8.We can ... Read More

In this problem, we have a binary tree with a path from the root node to the leaf node that is completely defined. The sum of all nodes from a root node to a leaf node must be greater than or equal to k. So we need to remove all nodes in the paths whose sum is less than k. An important thing to remember here is that a node may be a part of many paths, so only remove such nodes if all the paths have sum < k.From the root node to the leaf node, we can calculate ... Read More

Suppose we have an array A with m elements and another number n. Amal decided given a present for his n friend, so he will give each of them a jigsaw puzzle. The shop assistant told him that there are m puzzles in the shop, but they might differ in difficulty and size. Specifically, the ith jigsaw puzzle consists of A[i] pieces. So Amal decided that the difference between the numbers of pieces in his presents must be as small as possible. Let x be the number of pieces in the largest puzzle that he buys and y be the ... Read More

Suppose we have an array A with n elements. A[i] represents there are A[i] number of blocks stacked on top of each other at ith column. The entire blocks are inside a closed transparent boundary box. Now if we rotate the entire big box clockwise 90°, then due to change of gravity direction, the blocks will fall, after than reverse it to its previous orientation. Then find the new array like A after these operations.Problem CategoryThis problem falls under sorting problems. Sorting is a very common problem while we are talking about different problem solving algorithms in computer science. As ... Read More