/**
* NAME: regular_mult
* INPUT: MATRIX* m1, MATRIX* m2, MATRIX* res
* USAGE: Multiplies m1 and m2 naively and stores the result in res.
*
* NOTES: pointers for m1, m2, m3 must all be malloced before using this function.
*/
void regular_mult(MATRIX* m1, MATRIX* m2, MATRIX* res)
{
// Checks to see whether m1 and m2 can be multiplied.
if (m1->numCols != m2->numRows)
{
printf("Error: Matrices cannot be multiplied");
return;
}
// Define numRows and numCols of res
int rowSize = m1->numRows;
int colSize = m2->numCols;
// Fill in matrix information
res->numRows = rowSize;
res->numCols = colSize;
// Allocate memory for the rows of the matrix.
res->matrix = (BIGNUM**) malloc(rowSize * sizeof(BIGNUM*));
for(int i = 0; i < rowSize; i++)
{
// Allocate memory for each entry in the matrix.
res->matrix[i] = (BIGNUM*) malloc(colSize * sizeof(BIGNUM));
// Go across the columns of m2
for (int j=0; j< colSize; j++)
{
// Initialize a temporary bignum to store a sum.
BIGNUM* sum = malloc(sizeof(BIGNUM));
bignum_from_int(0,sum);
// Go down the rows of m1 and across the columns of m2.
// Naive multiplication is performed here.
for (int k = 0; k < m1->numCols; k++)
{
// Initialize a temporary bignum to store the result of multiplication.
BIGNUM* multRes = malloc(sizeof(BIGNUM));
bignum_from_int(0,multRes);
mult_bignums(&m1->matrix[i][k], &m2->matrix[k][j], multRes);
// Initialize a temporary bignum for addition.
BIGNUM* addRes = malloc(sizeof(BIGNUM));
bignum_from_int(0,addRes);
add_bignums(multRes, sum, addRes);
// Store the addition and free varibles.
*sum = *addRes;
free(multRes);
free(addRes);
}
// Store the sum into the matrix and free temp bignum.
res->matrix[i][j] = *sum;
free(sum);
}
}
}
int main() {
char *in_string;
bignum *sum = make_bignum_with_length( 0 );
while( scanf( "%s", in_string ) != EOF ) {
sum = add_bignums( make_bignum( in_string ), sum );
}
print_bignum( sum );
}
