1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
|
#include <iostream>
double** inputMatrix(unsigned int& rows, unsigned int& cols) {
std::cin >> rows >> cols;
double** mat = new double*[rows];
for (unsigned int row = 0; row < rows; row++) {
mat[row] = new double[cols];
for (unsigned int col = 0; col < cols; col++)
std::cin >> mat[row][col];
}
/* Използваме динамична памет, тя не се унищожава (освобождава)
* автоматично, което означава че можем да върнем указателя и
* всичко ще работи коректно.
*/
return mat;
}
void deleteMatrix(double** mat, unsigned int rows) {
for (unsigned int row = 0; row < rows; row++)
delete[] mat[row];
delete[] mat;
}
int main() {
unsigned int rowsA, colsA, rowsB, colsB;
double** matA = inputMatrix(rowsA, colsA), **matB = inputMatrix(rowsB, colsB);
if (colsA != rowsB) {
std::cout << "Cannot multiply!" << std::endl;
}
else {
double** matC = new double*[rowsA];
for (unsigned int row = 0; row < rowsA; row++) {
matC[row] = new double[colsB];
for (unsigned int col = 0; col < colsB; col++) {
matC[row][col] = 0;
for (unsigned int i = 0; i < colsA; i++) {
matC[row][col] += matA[row][i] * matB[i][col];
}
}
}
for (unsigned int row = 0; row < rowsA; row++) {
for (unsigned int col = 0; col < colsB; col++)
std::cout << matC[row][col] << ' ';
std::cout << std::endl;
}
deleteMatrix(matC, rowsA);
}
deleteMatrix(matA, rowsA);
deleteMatrix(matB, rowsB);
return 0;
}
|
