Multiply Matrices

This algorithm multiplies two given matrices

									/*****Please include following header files*****/
// stdlib.h
/***********************************************/

typedef struct {
	int** Matrix;
	int Rows;
	int Columns;
} Matrix;

int** CreateMatrix(int rowCount, int colCount) {
	int** matrix = (int**)malloc(sizeof(int*) * rowCount);

	for (int i = 0; i < rowCount; ++i) {
		matrix[i] = (int*)malloc(sizeof(int) * colCount);
	}

	return matrix;
}

Matrix MultiplyMatrices(Matrix firstMatrix, Matrix secondMatrix) {
	int** mult = CreateMatrix(firstMatrix.Rows, secondMatrix.Columns);

	if (firstMatrix.Columns != secondMatrix.Rows)
		return{ NULL, 0, 0 };

	for (int i = 0; i < firstMatrix.Rows; ++i)
		for (int j = 0; j < secondMatrix.Columns; ++j)
		{
			mult[i][j] = 0;
		}

	for (int i = 0; i < firstMatrix.Rows; ++i)
		for (int j = 0; j < secondMatrix.Columns; ++j)
			for (int k = 0; k < firstMatrix.Columns; ++k)
			{
				mult[i][j] += firstMatrix.Matrix[i][k] * secondMatrix.Matrix[k][j];
			}

	return{ mult, firstMatrix.Rows, secondMatrix.Columns };
}

Example

									int** m1 = CreateMatrix(2, 3);
m1[0][0] = 3;
m1[0][1] = -2;
m1[0][2] = 5;
m1[1][0] = 3;
m1[1][1] = 0;
m1[1][2] = 4;

int** m2 = CreateMatrix(3, 2);
m2[0][0] = 2;
m2[0][1] = 3;
m2[1][0] = -9;
m2[1][1] = 0;
m2[2][0] = 0;
m2[2][1] = 4;

Matrix matrix1 = { m1, 2, 3 };
Matrix matrix2 = { m2, 3, 2 };
Matrix sumMatrix = MultiplyMatrices(matrix1, matrix2);

Output

									[0][0] = 24
[0][1] = 29
[1][0] = 6
[1][1] = 25