A sly knapsack problem in disguise! Thanks to https://github.com/bhajunsingh/programming-challanges/tree/master/hackerrank/algorithms/the-indian-jobLesson learnt: The Italian\Indian job is two-way 01 Knapsack. And some complext problem can be convert…
reference: 6.4 knapsack in Algorithms(算法概论), Sanjoy Dasgupta University of California, San Diego Christos Papadimitriou University of California at Berkeley Umesh Vazirani University of California at Berkeley the unbounded knapsack and 0-1 knapsack a…
Problem Introduction Given a set of items and total capacity of a knapsack,find the maximal value of fractions of items that fit into the knapsack. Problem Description Task.The goal of this code problem is to implement an algorithm for the fractional…
Firt thought: an variation to LCS problem - but this one has many tricky detail. I learnt the solution from this link:https://github.com/wangyongliang/Algorithm/blob/master/hackerrank/Strings/Square%20Subsequences/main.cc And here is his code with my…
It is about how to choose btw. BFS and DFS. My init thought was to DFS - TLE\MLE. And its editorial gives a very neat BFS based idea which costs much less memory. https://www.hackerrank.com/challenges/beautiful-path/editorial…
It is marked as a NPC problem. However from the #1 code submission (https://www.hackerrank.com/CharlesOfria), it looks pretty much like a Brutal-Force (or simulation) based solution, mixed with some greedy strategies. To me the other NPC "Queens Revi…
http://acm.fzu.edu.cn/problem.php?pid=2214 Problem Description Given a set of n items, each with a weight w[i] and a value v[i], determine a way to choose the items into a knapsack so that the total weight is less than or equal to a given limit B a…
传送门 今天在HackerRank上翻到一道高精度题,于是乎就写了个高精度的模板,说是模板其实就只有乘法而已. Extra long factorials Authored by vatsalchanana on Jun 16 2015 Problem Statement You are given an integer N. Print the factorial of this number. N!=N×(N−1)×(N−2)×⋯×3×2×1 Note: Factorials of N>20…
http://acm.fzu.edu.cn/problem.php?pid=2214 Accept: 4 Submit: 6Time Limit: 3000 mSec Memory Limit : 32768 KB Problem Description Given a set of n items, each with a weight w[i] and a value v[i], determine a way to choose the items into a knapsa…
Description 题目描述 Given a set of n items, each with a weight w[i] and a value v[i], determine a way to choose the items into a knapsack so that the total weight is less than or equal to a given limit B and the total value is as large as possible. Find…
Great learning for me:https://www.hackerrank.com/rest/contests/master/challenges/lucky-numbers/hackers/turuthok/download_solution Basically it is memorized search application. And we follow a discrete strategy: split it into digits and go digit by di…
A variation to 0-1 Knapsack. (No Python code got fully AC. Python is too slow for this problem) #include <cmath> #include <cstdio> #include <vector> #include <iostream> #include <algorithm> using namespace std; int main() { /…
This is 'Difficult' - I worked out it within 45mins, and unlocked HackerRank Algorithm Level 80 yeah! So the idea is straight forward: 1. sort the input array and calculate partial_sum()2. find the negative\positive boundary with the accumulated give…
The most interesting, flexible and juicy binary tree problem I have ever seen. I learnt it from here: https://codepair.hackerrank.com/paper/5fIoGg74?b=eyJyb2xlIjoiY2FuZGlkYXRlIiwibmFtZSI6IkJsdWVCaXJkMjI0IiwiZW1haWwiOiJoZWFsdGh5dG9ueUBnbWFpbC5jb20ifQ%…
Something to learn: Rotation ops in AVL tree does not require recursion. https://github.com/andreimaximov/hacker-rank/blob/master/data-structures/tree/self-balancing-tree/main.cpp node *create_node(int val) { node *pNew = new node; pNew->val = val; p…
https://www.hackerrank.com/contests/infinitum-aug14/challenges/jim-beam 学习了线段相交的判断法.首先是叉乘,叉乘的几何意义是有向的平行四边形的面积(除以2就是三角形的面积).如果ABD和ABC正负相反,说明C和D在AB两侧,同样的,再判断A和B是否在CD两侧即可.当某三角形面积为0时,需要判断是否在线段上. #include <iostream> using namespace std; typedef long long…
https://www.hackerrank.com/challenges/service-lane 用RMQ做的,其实暴力也能过~ #include <iostream> #include <vector> #include <cmath> using namespace std; int main() { int n, t; cin >> n >> t; vector<int> vec(n); for (int i = 0; i…
https://www.hackerrank.com/contests/w1/challenges/maximizing-xor/ 找了半天规律,答案竟然是暴力,伤感.我找到的方法是利用规律2^x XOR 2^x - 1会最大,感觉稍微效率高点. int maxXor(int l, int r) { if (l == r) return 0; int p = 1; for (int i = 0; i <= 10; i++) { if (p * 2 > r) break; p *= 2; } i…
https://www.hackerrank.com/contests/w2/challenges/manasa-and-stones 简单题. #include<iostream> using namespace std; int main() { int T; cin >> T; while (T--) { int n, a, b; cin >> n >> a >> b; // a < b if ( a > b) { int tm…
https://www.hackerrank.com/contests/w4/challenges/crush 第一眼觉得要用线段树,但据说会超时.其实这个可以通过生成pair排序来做. #include <vector> #include <cstdlib> #include <algorithm> #include <iostream> using namespace std; int main() { int N, M; cin >> N…
https://www.hackerrank.com/contests/w5/challenges/closest-number 简单题. #include <iostream> #include <cmath> using namespace std; int main() { int T; cin >> T; while (T--) { int a, b, x; cin >> a >> b >> x; if (b < 0 &…
