1573. Number of Ways to Split a String
Given a binary string s (a string consisting only of ‘0’s and ‘1’s), we can split s into 3 non-empty strings s1, s2, s3 (s1+ s2+ s3 = s).
Return the number of ways s can be split such that the number of characters ‘1’ is the same in s1, s2, and s3.
Since the answer may be too large, return it modulo 10^9 + 7.
Implement pow(x, n), which calculates x raised to the power n (i.e. xn).
1648. Sell Diminishing-Valued Colored Balls
You have an inventory of different colored balls, and there is a customer that wants orders balls of any color.
The customer weirdly values the colored balls. Each colored ball’s value is the number of balls of that color you currently have in your inventory. For example, if you own 6 yellow balls, the customer would pay 6 for the first yellow ball. After the transaction, there are only 5 yellow balls left, so the next yellow ball is then valued at 5 (i.e., the value of the balls decreases as you sell more to the customer).
You are given an integer array, inventory, where inventory[i] represents the number of balls of the ith color that you initially own. You are also given an integer orders, which represents the total number of balls that the customer wants. You can sell the balls in any order.
Return the maximum total value that you can attain after selling orders colored balls. As the answer may be too large, return it modulo 109 + 7.
1540. Can Convert String in K Moves
Given two strings s and t, your goal is to convert s into t in k moves or less.
During the ith (1 <= i <= k) move you can:
- Choose any index j (1-indexed) from s, such that 1 <= j <= s.length and j has not been chosen in any previous move, and shift the character at that index i times.
- Do nothing.
Shifting a character means replacing it by the next letter in the alphabet (wrapping around so that ‘z’ becomes ‘a’). Shifting a character by i means applying the shift operations i times.
Remember that any index j can be picked at most once.
Return true if it’s possible to convert s into t in no more than k moves, otherwise return false.
Given an integer array nums, reorder it such that nums[0] < nums[1] > nums[2] < nums[3]….
You may assume the input array always has a valid answer.
Given an array of n integers nums, a 132 pattern is a subsequence of three integers nums[i], nums[j] and nums[k] such that i < j < k and nums[i] < nums[k] < nums[j].
Return true if there is a 132 pattern in nums, otherwise, return false.
Follow up: The O(n^2) is trivial, could you come up with the O(n logn) or the O(n) solution?
1487. Making File Names Unique
Given an array of strings names of size n. You will create n folders in your file system such that, at the ith minute, you will create a folder with the name names[i].
Since two files cannot have the same name, if you enter a folder name which is previously used, the system will have a suffix addition to its name in the form of (k), where, k is the smallest positive integer such that the obtained name remains unique.
Return an array of strings of length n where ans[i] is the actual name the system will assign to the ith folder when you create it.
Given a list of non-negative integers nums, arrange them such that they form the largest number.
Note: The result may be very large, so you need to return a string instead of an integer.
Given two version numbers, version1 and version2, compare them.
Version numbers consist of one or more revisions joined by a dot ‘.’. Each revision consists of digits and may contain leading zeros. Every revision contains at least one character. Revisions are 0-indexed from left to right, with the leftmost revision being revision 0, the next revision being revision 1, and so on. For example 2.5.33 and 0.1 are valid version numbers.
To compare version numbers, compare their revisions in left-to-right order. Revisions are compared using their integer value ignoring any leading zeros. This means that revisions 1 and 001 are considered equal. If a version number does not specify a revision at an index, then treat the revision as 0. For example, version 1.0 is less than version 1.1 because their revision 0s are the same, but their revision 1s are 0 and 1 respectively, and 0 < 1.
Return the following:
- If version1 < version2, return -1.
- If version1 > version2, return 1.
- Otherwise, return 0.
1353. Maximum Number of Events That Can Be Attended
Given an array of events where events[i] = [startDayi, endDayi]. Every event i starts at startDayi and ends at endDayi.
You can attend an event i at any day d where startTimei <= d <= endTimei. Notice that you can only attend one event at any time d.
Return the maximum number of events you can attend.