Printer-friendly version

using namespace std;

const int MAX=5;

void matMult(int A[][MAX], double B[][MAX],
     double C[][MAX], int rowsA, int colsA,
     int rowsB, int colsB, int &rowsC, int &colsC);

int main()
{
   int i, j, ntype, ncomp, rowsC, colsC;
   int comp[MAX][MAX];
   double cost[MAX][MAX] ;
   double radio[MAX][MAX];

   cout << "Enter the number of radio types: ";
   cin >> ntype;
   cout << "Enter the number of components: ";
   cin >> ncomp;

   // input component data

   cout << "For each type, enter the number of capacitors, resistors, and transistors\n";
   for (i = 0; i < ntype; i++)
     for (j = 0; j < ncomp; j++)
       cin >> comp[i][j];

   cout << "Enter the cost of capacitors, resistors, and transistors: ";
   cin >> cost[0][0] >> cost[1][0] >> cost[2][0];

   // call matrix multiply routine to calculate radio costs

   matMult( comp, cost, radio, ntype, ncomp, ncomp, 1, rowsC, colsC);

   // display results

   cout << setiosflags(ios::showpoint | ios::fixed) << setprecision(2);

   for(i = 0; i < ntype; i++)
     cout << "Radio type " << i+1 << " costs $" << radio[i][0] << endl;

   return 0;
}

// matrix multiply function
void matMult(int A[][MAX], double B[][MAX],
     double C[][MAX], int rowsA, int colsA,
     int rowsB, int colsB, int &rowsC, int &colsC)
{
  int i, j, k;

  if(colsA != rowsB)
  {
    cout << "Error: cols A must = rows B/n";
    exit(1);
  }
 
  rowsC = rowsA;
  colsC = colsB;

  for(i = 0; i < rowsA; i++)
    for(j = 0; j < colsB; j++)
    {
       C[i][j] = 0.0;
       for(k=0; k < colsA; k++)
          C[i][j] += A[i][k] * B[k][j];
    }

  return;
}
% g++ radioMat.cpp
% a.out
Enter the number of radio types: 4
Enter the number of components: 3
For each type, enter the number of capacitors, resistors, and transistors
2 6 3
6 11 5
13 29 10
8 14 7
Enter the cost of capacitors, resistors, and transistors: .35 .2 1.40
Radio type 1 costs $6.10
Radio type 2 costs $11.30
Radio type 3 costs $24.35
Radio type 4 costs $15.40