Suppose we have a number n. We have to find the least positive value x such that x is made up of only two digits 9's and 0's, and x is multiple of n.So, if the input is like n = 26, then the output will be 90090.To solve this, ... Read More

Suppose we have a list of elements called nums, we have to check whether all numbers appear even times or not. We have to solve it using constant space.So, if the input is like nums = [8, 9, 9, 8, 5, 5], then the output will be True, because all ... Read More

Suppose we have a list of numbers called nums, we have to check whether there is an element whose frequency is same as its value.So, if the input is like nums = [2, 5, 7, 5, 3, 5, 3, 5, 9, 9, 5], then the output will be True, because ... Read More

Suppose we have a list of numbers called nums. We have to find the number of pairs i < j such that nums[i] and nums[j] are same.So, if the input is like nums = [5, 4, 5, 4, 4], then the output will be 4, as We have index pairs ... Read More

Suppose we have a set of Cartesian points in a list called points. We have to sort them based on their polar angles. The polar angles vary in range 0 and 2*PI. If some points have same polar angles, then arrange them based on the distance of that point from ... Read More

Suppose we have a list of elements called nums of size n + 1, they are selected from range 1, 2, ..., n. As we know, by pigeonhole principle, there must be a duplicate. We have to find the duplicate. Here our target is to find the task in O(n) ... Read More

Suppose we have a list of numbers say nums, we have to find the number of elements x in the array, such that x + 1 also exists in the array.So, if the input is like nums = [4, 2, 3, 3, 7, 9], then the output will be 3, ... Read More

Suppose we have a list of queries Q, where each query Q[i] contains a triplet [a_i, b_i and d_i]. Consider we are at position (0, 0) initially, then in one step we can move from some position (x1, y1) to (x2, y2) where Euclidean distance between these two points is ... Read More

Suppose we have a list of numbers called nums that contains at least one element whose value is 1. We have to check whether all the 1s appear consecutively or not.So, if the input is like nums = [8, 2, 1, 1, 1, 3, 5], then the output will be ... Read More

Suppose we have an array called nums holding n-1 arithmetic sequence terms. One element except the first or last element of nums was removed before. We have to find the removed number.So, if the input is like nums = [5, 7, 11, 13], then the output will be 9 because, ... Read More