Problems
October 4, 2022
Palindrome number
We can convert the number to string, reverse it and then check whether it's palindrome of not.
Time Complexity: O(n)
Space Complexity: O(n)
First of all it the number...
October 4, 2022
Ugly number
If the number is negative, then it's not a ugly number. Then we do exactly what the problem statement says, we divide the number by 2, 3 and 5 until we can't divide it any more with these numbers. If...
ReadOctober 3, 2022
Minimum time to make rope colorful
For a group of continuous same characters, we need to delete all the group but leave only one character. For each group of continuous same characters, we need cost = sum_cost(group) -...
ReadOctober 3, 2022
Asteroid collision
We will take a stack and iterate over all the elements. If the element is positive, we append it on the stack. Else we take the number, check the value of the number. If it is equal to the top of the...
ReadOctober 2, 2022
Minimum difference between highest and lowest of k scores
We will first sort the elements and then loop over all the elements and take the difference between k elements, and keep a running minimum and then return that as result. Time Complexity:...
ReadOctober 2, 2022
Number of dice rolls with target sum
We will take the brute force method to solve the problem, in every iteration till n, we will take 1 to k elements and add it to our total recursively. Then when we reach the target, we will add it to...
ReadOctober 2, 2022
Rotate array
This approach is based on the fact that when we rotate the array k times, k%nk elements from the back end of the array come to the front and the rest of the elements from the front shift backwards....
ReadOctober 2, 2022
Move zeroes
We will take a simple two pointers approach, the left will be the first index. Then we iterate over the array, and every time we find a zero, we change the position of it with the next character...
ReadOctober 1, 2022
Valid palindrome II
We will take two pointers, one at the beginning and one at the end. Then we start compare, if it doesn't match, then we try to skip the character in the left pointer and character in right pointer...
ReadOctober 1, 2022
Intersection of two linked lists
We start from both list together, and if we can't find a match, we change the position of the both list, and continue until we find a match and return that.
Time Complexity: O(n)...