## [Leetcode]640. Solve the Equation

Solve a given equation and return the value of x in the form of string "x=#value". The equation contains only '+', '-' operation, the variable x and its coefficient.
If there is no solution for the equation, return "No solution".
If there are infinite solutions for the equation, return "Infinite solutions".
If there is exactly one solution for the equation, we ensure that the value of x is an integer.

Continue reading “[Leetcode]640. Solve the Equation”

## [Leetcode]1558. Minimum Numbers of Function Calls to Make Target Array

Your task is to form an integer array nums from an initial array of zeros arr that is the same size as nums.
Return the minimum number of function calls to make nums from arr.
The answer is guaranteed to fit in a 32-bit signed integer.
Continue reading “[Leetcode]1558. Minimum Numbers of Function Calls to Make Target Array”

## [Leetcode]739. Daily Temperatures

Given a list of daily temperatures T, return a list such that, for each day in the input, tells you how many days you would have to wait until a warmer temperature. If there is no future day for which this is possible, put 0 instead.
For example, given the list of temperatures T = [73, 74, 75, 71, 69, 72, 76, 73], your output should be [1, 1, 4, 2, 1, 1, 0, 0].
Note: The length of temperatures will be in the range [1, 30000]. Each temperature will be an integer in the range [30, 100].

## [Leetcode]1574. Shortest Subarray to be Removed to Make Array Sorted

Given an integer array arr, remove a subarray (can be empty) from arr such that the remaining elements in arr are non-decreasing.
A subarray is a contiguous subsequence of the array.
Return the length of the shortest subarray to remove.
Continue reading “[Leetcode]1574. Shortest Subarray to be Removed to Make Array Sorted”

## [Leetcode]835. Image Overlap

Two images A and B are given, represented as binary, square matrices of the same size.  (A binary matrix has only 0s and 1s as values.)
We translate one image however we choose (sliding it left, right, up, or down any number of units), and place it on top of the other image.  After, the overlap of this translation is the number of positions that have a 1 in both images.
(Note also that a translation does not include any kind of rotation.)
What is the largest possible overlap?
Notes:
1 <= A.length = A[0].length = B.length = B[0].length <= 30
0 <= A[i][j], B[i][j] <= 1

## [Leetcode]714. Best Time to Buy and Sell Stock with Transaction Fee

This series of Buy and Sell Stock I~VI on Leetcode is a great practice for Dynamic Programming – State Machine. Therefore I prepared blogs for each of them and hopefully it would help you to understand them better. You can find the relations of them at the bottom and feel free to leave any comments.

Continue reading “[Leetcode]714. Best Time to Buy and Sell Stock with Transaction Fee”

## [Leetcode]309. Best Time to Buy and Sell Stock with Cooldown

This series of Buy and Sell Stock I~VI on Leetcode is a great practice for Dynamic Programming – State Machine. Therefore I prepared blogs for each of them and hopefully it would help you to understand them better. You can find the relations of them at the bottom and feel free to leave any comments.

Continue reading “[Leetcode]309. Best Time to Buy and Sell Stock with Cooldown”

## [Leetcode]1286. Iterator for Combination

Design an Iterator class, which has:
A constructor that takes a string characters of sorted distinct lowercase English letters and a number combinationLength as arguments.
A function next() that returns the next combination of length combinationLength in lexicographical order.
A function hasNext() that returns True if and only if there exists a next combination.
Constraints:
1 <= combinationLength <= characters.length <= 15
There will be at most 10^4 function calls per test.
It's guaranteed that all calls of the function next are valid.
Continue reading “[Leetcode]1286. Iterator for Combination”