Suppose we have a 2d matrix. We have to check whether we can start from some cell then move adjacent cells (up, down, left, right) of the same value, and come back to the same starting point. We cannot revisit a cell that we have visited last.So, if the input ... Read More

Suppose we have a binary matrix and another value k. You want to split the matrix into k pieces such that each piece contains at least one 1 in it. But there are some rules for cutting, we have to follow in order: 1. Select a direction: vertical or horizontal ... Read More

Suppose we have a string s, we have to check whether we can make this string a palindrome after deleting at most k characters or not.So, if the input is like s = "lieuvrel", k = 4, then the output will be True, we can delete three characters to get ... Read More

Suppose we have a list of numbers called nums, we have to rearrange its order to form the largest possible number and return that as a string.So, if the input is like nums = [20, 8, 85, 316], then the output will be "88531620".To solve this, we will follow these ... Read More

Consider a country that is represented as a tree with N nodes and N-1 edges. Now each node represents a town, and each edge represents a road. We have two lists of numbers source and dest of size N-1. According to them the i-th road connects source[i] to dest[i]. And ... Read More

Suppose we have a list of numbers called nums and another value k, we have to find the number of subsets in the list that sum up to k. If the answer is very large then mod this with 10^9 + 7So, if the input is like nums = [2, ... Read More

Suppose we have a binary matrix. Now consider an operation where we take one cell and flip it and all its neighboring cells (up, down, left, right). We have to find the minimum number of operations required such that matrix contains only 0s. If there is no solution, then return ... Read More

Suppose we have a list of cartesian points [(x1, y1), (x2, y2), ..., (xn, yn)], that is representing a polygon, and also have two values x and y, we have to check whether (x, y) lies inside this polygon or on the boundary.So, if the input is like points = ... Read More

Suppose we have a list of numbers called nums, we have to find the length of the longest increasing subsequence and we are assuming the subsequence can wrap around to the beginning of the list.So, if the input is like nums = [6, 5, 8, 2, 3, 4], then the ... Read More

Suppose we have a N x N binary matrix where 0 is for empty cells and 1 is a blocked cells, we have to find the number of ways to choose N empty cells such that every row and every column has at least one chosen cells. If the answer ... Read More