Suppose we have two lists of numbers of same length called performance and costs. And we also have another number k. These indicates that each worker i performs at performance[i] level and it takes costs at least costs[i]. We have to find the minimum cost to hire k employees given ... Read More

Suppose we have a string s, we have to find the number of non-empty unique subsequences of s. If the answer is very large then mod the result by 10^9 + 7.So, if the input is like s = "xxy", then the output will be 5, as there are five ... Read More

Suppose we have a 2d binary matrix, we have to find the number of distinct islands in the given matrix. Here 1 represents land and 0 represents water, so an island is a set of 1s that are close and whose perimeter is surrounded by water. Here two islands are ... Read More

Suppose we have a strings s. The s is containing digits from 0 - 9 and we also have another number k. We have to find the number of different ways that s can be represented as a list of numbers from [1, k]. If the answer is very large ... Read More

Suppose we have a 2D matrix with 3 possible values −0 for an empty cell.1 for a coin.−1 for a wall.We have to find the maximum number of coins we can take by starting from the top−left cell and reaching the bottom−right cell by moving only right or down direction. ... Read More

Suppose two players are playing a game. Where several candies placed on a line, and person 1 is given a list of numbers called nums that is representing the point value of each candy. On each person's turn, they can pick 1, 2, or 3 candies from the front of ... Read More

Suppose we have a list of numbers called candies and two persons are racing to collect the most number of candies. Here the race is turn based, person 1 is starting first, and in each turn he can pick up candies from the front or from the back. We have ... Read More

Suppose we have a list of numbers called nums. We have to find the number of permutations of nums such that sum of every pair of adjacent values is a perfect square. Two permutations A and B are unique when there is some index i where A[i] is not same ... Read More

Suppose we have two strings s, t, and another string r we have to check whether there is any way to get r by merging characters in order from s and t.So, if the input is like s = "xyz" t = "mno" r = "xymnoz", then the output will ... Read More

Suppose we have a lowercase string s with letters x and y. Now consider an operation in which we change a single x to y or vice versa. We have to find the minimum number of times we need to perform that operation to set all x's come before all ... Read More