# [LeetCode 77] Combinations [Java]

**2018-02-28

1. Description Given two integers n and k, return all possible combinations of k numbers out of 1 ... n. 2. Example If n = 4 and k = 2, a soluti...

1. Description Given two integers n and k, return all possible combinations of k numbers out of 1 ... n. 2. Example If n = 4 and k = 2, a soluti...

1. Description Given two binary strings, return their sum (also a binary string). 2. Example a = "11" b = "1" Return "100". 3.Code public c...

1. Description Given a non-negative integer represented as a non-empty array of digits, plus one to the integer. You may assume the integer do not ...

1. Description Validate if a given string is numeric. Note: It is intended for the problem statement to be ambiguous. You should gather all require...

1. Description The set [1,2,3,…,n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order, We get the...

1. Description Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers. If such arrange...

1. Description Given a collection of numbers that might contain duplicates, return all possible unique permutations. 2. Example [1,1,2] have the...

1. Description Given two non-negative integers num1 and num2 represented as strings, return the product of num1 and num2. Note: The length of bo...

1. Description Divide two integers without using multiplication, division and mod operator. If it is overflow, return MAX_INT. 2. Code public class...

1. Description Given a string representing an expression of fraction addition and subtraction, you need to return the calculation result in string ...