Given n unique integers, number k (1<=k<=n) and target. Find all possible k integers where their sum is target. Example Given [1,2,3,4], k=2, target=5, [1,4] and [2,3] are possible solutions. 这道题同Combination Sum II public class Solution { /** * @par…

K SUM My Submissions http://www.lintcode.com/en/problem/k-sum/ 题目来自九章算法 13% Accepted Given n distinct positive integers, integer k (k <= n) and a number target. Find k numbers where sum is target. Calculate how many solutions there are? Example Given…

题目: k数和 II 给定n个不同的正整数,整数k(1<= k <= n)以及一个目标数字. 在这n个数里面找出K个数,使得这K个数的和等于目标数字,你需要找出所有满足要求的方案. 样例 给出,返回 [[1,4],[2,3]] 解题: 题目中限制的条件很多,A数组中的各个数字都不相等,A中k个数的和是 target 问题: 1.在所有的组合方式中,A[i] 是否会重复,也就是说,A[i] ,即在{a,b,A[i]} 也在{a1,b1,A[i]}中. 可能:如A = {1,2,3,4,5} 3个…

Given an integer array in the construct method, implement two methods query(start, end) and modify(index, value): For query(start, end), return the sum from index start to index end in the given array. For modify(index, value), modify the number in t…

Great great DP learning experience:http://www.cnblogs.com/yuzhangcmu/p/4279676.html Remember 2 steps of DP: a) setup state transfer equation; b) setup selection strategy. a) States From problem statement, we find 3 variables: array size, k and target…

C++ DFS class Solution { public: void help(vector<int> &a, int now, int sum, int target, vector<int> &path, vector<vector<int> > &ans, bool last) { if (sum > target) { return ; } if (now >= a.size()) { if (sum ==…

Sliding window doesn't work. So it is a typical partial_sum base solution. As below. However if you use a balanced binary search tree, you can get O(nlgn) - like std::set<int> class Solution { public: /** * @param A an integer array * @param start a…

k Sum Given n distinct positive integers, integer k (k <= n) and a number target. Find k numbers where sum is target. Calculate how many solutions there are? Example Given [1,2,3,4], k = 2, target = 5. There are 2 solutions: [1,4] and [2,3]. Return 2…

Subarray Sum Given an integer array, find a subarray where the sum of numbers is zero. Your code should return the index of the first number and the index of the last number. Example Given [-3, 1, 2, -3, 4], return [0, 2] or [1, 3]. 用hashmap来存从nums[0…

Continuous Subarray Sum II   Given an circular integer array (the next element of the last element is the first element), find a continuous subarray in it, where the sum of numbers is the biggest. Your code should return the index of the first number…