MSVCRTD.lib(crtexew.obj) : error LNK2019: unresolved external symbol WinMain@16 referenced in function __tmainCRTStartup

#include <iostream>
 using namespace std;
 int main()
 {
  const double A = 15.0, 
  B = 12.0, 
  C = 9.0;
  double aTotal, bTotal, cTotal, total;
  int numSold;
 
  cout << "Enter The Number of Class A Tickets Sold: ";
  cin >> numSold;
  aTotal = numSold * A;
 
  cout << "Enter The Number of Class B Tickets Sold: ";
  cin >> numSold;
  bTotal = numSold * B;
 
  cout << "Enter The Number of Class C Tickets Sold: ";
  cin >> numSold;
  cTotal = numSold * C;
 
  total = aTotal + bTotal + cTotal;
 
  cout << "Income Generated" << endl;
  cout << "From Class A Seats [codesample]quot; << aTotal << endl;
  cout << "From Class B Seats [codesample]quot; << bTotal << endl;
  cout << "From Class C Seats [codesample]quot; << cTotal << endl;
  cout << "-----------------------" << endl;
  cout << "Total Income: " << total << endl;
 
  return 0;
 }