一、问题设A1,A2,…,An为n个矩阵的序列,其中Ai为Pi-1*P为阶矩阵,这个矩阵链的输入用向 量P=<P0,P1,…Pn> 给出。二、解析 r表示问题规模长度,r=1表示矩阵自身相乘,由于是自身相乘,表示为0,r=2表示两个两个矩阵相乘,如m[1][2]表示A1A2,为1020*5数组m表示矩阵相乘,s[i][j]=k,表示在k后加括号...
矩阵链乘(Matrix Chain Multiplication) 输入n个矩阵的维度和一些矩阵链乘表达式,输出乘法的次数。如果乘法无法进行,则输出error。假定A是m*n矩阵,B是n*p矩阵,那么A*B是m*p矩阵,乘法次数为m*n*p。如果A的列数不等于B的行数,则乘法无法进行。 例如,A是50*10的,B是10*20的,C是20*5的,则(A(BC))的乘法...
#include<cstring> #include<stack> using namespace std; struct Matrix { int r; int c; char name; }; Matrix m[100]; int main() { int test; char str[100]; scanf("%d", &test); getchar(); for(int i = 0; i < test; i++) { scanf("%c", &(m[i].name)); scanf("%d",...
1.矩阵链乘 Matrix Chain Multiplication01-14 收起 题目链接: https://www.luogu.com.cn/problem/UVA442题意:给定若干个矩阵表达式,以及涉及到的矩阵的行与列 定义矩阵相乘次数为矩阵1的行数矩阵1的列数(矩阵2的行数)矩阵2的列数 计算每个表达式的矩阵相乘次数(若不满足矩阵乘法规律输出error)思路...
Suppose you have to evaluate an expression like A*B*C*D*E where A,B,C,D and E are matrices. Since matrix multiplication is associative, the order in which multiplications are performed is arbitrary. However, the number of elementary multiplications needed strongly depends on the evaluation orde...
#include<algorithm> using namespace std; struct Matrix{//定义矩阵类型的结构体 int a,b; Matrix(int a=0,int b=0):a(a),b(b){ } }m[26];//结构体数组 stack<Matrix>s;//运用到栈的知识; int main() { int n; cin>>n; for(int i=0;i<n;i++){ string name; cin>>name; ...
简介:UVA442 矩阵链乘 Matrix Chain Multiplication 题目描述 思路:首先要明白以下几点: 什么是矩阵乘法?(大概学过线代的都知道) 什么矩阵不可乘? A a*b B c*d 当 b = c时,两个矩阵可以相乘,同时结果为 C a*d 矩阵乘法的次数如何计算: 可以相乘的情况下 次数 = a*b*d (a*c*d也行) 这可以自己推...
Matrix Chain Multiplication Suppose you have to evaluate an expression like ABCDE where A,B,C,D and E are matrices. Since matrix multiplication is associative, the order in which multiplications are performed is arbitrary. Howev...442 - Matrix Chain Multiplication*** ......
Matrix chainMemory mappingDynamic programmingMemory optimized techniqueNumber of multiplications needed for Matrix Chain Multiplication of \\( n \\) matrices depends not only on the dimensions but also on the order to multiply the chain. The problem is to find the optimal order of multiplication. ...
Matrix Chain Multiplication Suppose you have to evaluate an expression like A*B*C*D*E where A,B,C,D and E are matrices. Since matrix multiplication is associative, the order in which multiplications are performed is arbitrary. However, the number of elementary multiplications needed strongly depe...