H. Degenerate Matrix Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/549/problem/H Description The determinant of a matrix 2 × 2 is defined as follows: A matrix is called degenerate if its determinant is equal to zero. The…

Problem Description As we know, sequence in the form of an=a1+(n−1)d is called arithmetic progression and sequence in the form of bn=b1qn−1(q>1,b1≠0) is called geometric progression. Huazheng wants to use these two simple sequences to generate a simp…

About this Course Machine learning is the science of getting computers to act without being explicitly programmed. In the past decade, machine learning has given us self-driving cars, practical speech recognition, effective web search, and a vastly i…

We have a two dimensional matrix A where each value is 0 or 1. A move consists of choosing any row or column, and toggling each value in that row or column: changing all 0s to 1s, and all 1s to 0s. After making any number of moves, every row of this…

We have a two dimensional matrix A where each value is 0 or 1. A move consists of choosing any row or column, and toggling each value in that row or column: changing all 0s to 1s, and all 1s to 0s. After making any number of moves, every row of this…

老久没更了,冬令营也延期了(延期后岂不是志愿者得上学了?) 最近把之前欠了好久的债,诸如FFT和Matrix-Tree等的搞清楚了(啊我承认之前只会用,没有理解证明--),FFT老多人写,而MatrixTree没人证我就写一下吧-- Matrix Tree结论 Matrix Tree的结论网上可多,大概一条主要的就是,图中生成树的数量等于 \(V-E\) 的任一余子式,其中: \(V\) 为对角阵,第 \(i\) 个元素为点 \(i\) 的度数 \(E\) 为对称阵,对角线为零且 \(E_{i,…

                             Matrix Multiplication Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 18173   Accepted: 3912 Description You are given three n × n matrices A, B and C. Does the equation A × B = C hold true? Input The first l…

Matrix Multiplication Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 17783   Accepted: 3845 Description You are given three n × n matrices A, B and C. Does the equation A × B = C hold true? Input The first line of input contains a posit…

Is it a fantastic matrix? Time Limit : 2000/1000ms (Java/Other)   Memory Limit : 65536/32768K (Java/Other) Total Submission(s) : 5   Accepted Submission(s) : 2 Problem Description Given an n*m matrix, you are asked to judge if it's fantastic. The rul…

We have a two dimensional matrix A where each value is 0 or 1. A move consists of choosing any row or column, and toggling each value in that row or column: changing all 0s to 1s, and all 1s to 0s. After making any number of moves, every row of this…