Given an array of positive integers nums, remove the smallest subarray (possibly empty) such that the sum of the remaining elements is divisible by p. It is not allowed to remove the whole array.
Return the length of the smallest subarray that you need to remove, or -1 if it’s impossible.
A subarray is defined as a contiguous block of elements in the array.
Given four integers n, a, b, and c, return the nth ugly number.
Ugly numbers are positive integers that are divisible by a, b, or c.
1654. Minimum Jumps to Reach Home
A certain bug’s home is on the x-axis at position x. Help them get there from position 0.
The bug jumps according to the following rules:
- It can jump exactly a positions forward (to the right).
- It can jump exactly b positions backward (to the left).
- It cannot jump backward twice in a row.
- It cannot jump to any forbidden positions.
The bug may jump forward beyond its home, but it cannot jump to positions numbered with negative integers.
Given an array of integers forbidden, where forbidden[i] means that the bug cannot jump to the position forbidden[i], and integers a, b, and x, return the minimum number of jumps needed for the bug to reach its home. If there is no possible sequence of jumps that lands the bug on position x, return -1.
Design your implementation of the linked list. You can choose to use a singly or doubly linked list.
A node in a singly linked list should have two attributes: val and next. val is the value of the current node, and next is a pointer/reference to the next node.
If you want to use the doubly linked list, you will need one more attribute prev to indicate the previous node in the linked list. Assume all nodes in the linked
list are 0-indexed.Implement the MyLinkedList class:
- MyLinkedList() Initializes the MyLinkedList object.
- int get(int index) Get the value of the indexth node in the linked list. If the index is invalid, return -1.
- void addAtHead(int val) Add a node of value val before the first element of the linked list. After the insertion, the new node will be the first node of the linked list.
- void addAtTail(int val) Append a node of value val as the last element of the linked list.
- void addAtIndex(int index, int val) Add a node of value val before the indexth node in the linked list. If index equals the length of the linked list, the node will be appended to the end of the linked list. If index is greater than the length, the node will not be inserted.
- void deleteAtIndex(int index) Delete the indexth node in the linked list, if the index is valid.
A good meal is a meal that contains exactly two different food items with a sum of deliciousness equal to a power of two.
You can pick any two different foods to make a good meal.
Given an array of integers deliciousness where deliciousness[i] is the deliciousness of the ith item of food, return the number of different good meals you can make from this list modulo 109 + 7.
Note that items with different indices are considered different even if they have the same deliciousness value.
1191. K-Concatenation Maximum Sum
Given an integer array arr and an integer k, modify the array by repeating it k times.
For example, if arr = [1, 2] and k = 3 then the modified array will be [1, 2, 1, 2, 1, 2].
Return the maximum sub-array sum in the modified array. Note that the length of the sub-array can be 0 and its sum in that case is 0.
As the answer can be very large, return the answer modulo 10^9 + 7.
Find the smallest prime palindrome greater than or equal to N.
Recall that a number is prime if it’s only divisors are 1 and itself, and it is greater than 1.
For example, 2,3,5,7,11 and 13 are primes.
Recall that a number is a palindrome if it reads the same from left to right as it does from right to left.
For example, 12321 is a palindrome.