Question

我正在编写一个程序，它接受两个不同矩阵的元素，然后它将它们相乘，接下来它将它们保存在一个多维数组中。但它只适用于方阵。（Visual Studio 2013没有错误。）如果您帮助我编辑此代码以便将各种矩阵相乘，我将很高兴。

    int a, b, c, d;
    int Mat1[10][10];
    int Mat2[10][10];
    int Mat3[10][10];
    Back1:
    cout << endl << "Enter the number of rows in Matrix 1 : ";
    cin >> a;
    cout << endl << "Enter the number of columns in Matrix 1 : ";
    cin >> b;
    cout << endl << "Enter the number of rows in Matrix 2 : ";
    cin >> c;
    cout << endl << "Enter the number of column in Matrix 2 : ";
    cin >> d;
    if (b != c) {
        cout << endl << "******************************************"
             << "\nThis type of Matrix can't be multiplied . " << endl;
        goto Back1;
    }
    for (int i = 0; i < a; i++) {
        for (int j = 0; j < b; j++) {
            cout << endl << "(MAT 1 ) \n\nEnter the Element of row " << i + 1
                 << " column " << j + 1 << " : ";
            cin >> Mat1[i][j];
        }
    }
    for (int i = 0; i < c; i++) {
        for (int j = 0; j < d; j++) {
            cout << endl << "(MAT 2 ) \n\nEnter the Element of row " << i + 1
                 << " column " << j + 1 << " : ";
            cin >> Mat2[i][j];
        }
    }
    for (int i = 0; i < a; i++) {
        for (int j = 0; j < d; j++) {
            Mat3[i][j] = Mat1[i][j] * Mat1[i][j];
        }
    }
    for (int i = 0; i < a; i++) {
        for (int j = 0; j < d; j++) {
            cout << setw(4) << Mat3[i][j] << setw(4);
        }
        cout << endl;
    }
}

Answer 1

你的矩阵乘法代码是错误的。而不是：

for (int i = 0; i < a; i++)
{
   for (int j = 0; j < d; j++)
   {
      Mat3[i][j] = Mat1[i][j] * Mat1[i][j];
   }
}

你需要：

for (int i = 0; i < a; i++)
{
   for (int j = 0; j < d; j++)
   {
      Mat3[i][j] = 0;
      for (int k = 0; k < c; k++)
      {
         Mat3[i][j] += Mat1[i][k] * Mat2[k][j];
      }
   }
}

用C ++乘以两个矩阵

1 个答案: