Can anyone tell me why I get an error on my last cout?

#include <iostream>
#include <cmath>
#include <stdio.h>
#include <cstring>
#include <conio.h>

using namespace std;
inline void keep_window_open() { char ch; cin>>ch; }

int main()
{
 cout << "How many pennies do you have?\n";
 int pennies;
 cin >> pennies;
 double total_pen;
 total_pen = (0.01 * pennies);
           if (pennies >= 1)
           {
                       string penn = " pennies.";
           }else
           {
                       string penn = " penny.";
 } cout << "How many nickles do you have?\n";
 int nickles;
 cin >> nickles;
 double total_nic;
 total_nic = (0.05 * nickles);
           if (nickles >= 1)
           {
                       string five = " nickels.";
           }else
           {
                       string five = " nickel.";
 } cout << "How many dimes do you have?\n";
 int dimes;
 cin >> dimes;
 double total_dim;
 total_dim = (0.10 * dimes);
           if (dimes >= 1)
           {
                     string ten = " dimes.";
           }else
           {
                     string ten = " dime."; 
 } cout << "How many quarters do you have?\n";
 int quarters;
 cin >> quarters;
 double total_qua;
 total_qua = (0.25 * quarters);
           if (quarters >= 1)
           {
                        string twentyfive = " quarters.";
           }else
           {
                        string twentyfive = " quarter.";
 } cout << "How many half-dollars do you have?\n";              
 int half_dollars;
 cin >> half_dollars;
 double total_dol;
 total_dol = (0.50 * half_dollars);
           if (half_dollars >= 1)
           { 
                        string fifty = " half dollars.";
           }else
           {
                        string fifty = " half dollar.";
           }
string saying = "You have ";
cout << saying pennies penn << "\n" << saying nickles five << "\n" << saying dimes ten << "\n" << saying quarters twentyfive << "\n" << saying half_dollars fifty << "\n"; 
keep_window_open()
return 0;
}