#include <iostream>
using namespace std;
 
int main()
{
	char input;
	char times[2];
	char again;
	int ans;
	do
	{
		cout<<"What character to use for the pattern?\n";
		input=cin.get();
		cin.ignore(1);
		cout<<"Your pattern will be "<<input<<endl;
		cout<<"How many lines(from 1 to 20)?\n";
		cin.getline(times,3);
		ans=atoi(times);
		cout<<"You will print "<<ans<<" lines with this pattern.\n";
		for (int x=0;x<ans;x++)
		{
			for (int y=0;y<=x;y++)
				cout<<input;
			cout<<endl;
		}
		for (int x=ans;x>0;x--)
		{
			for (int y=x;y>0;y--)
				cout<<input;
			cout<<endl;
		}
		cout<<"Run new pattern? (y or Y)\n";
		again=cin.get();
		cin.ignore(1);
	}while (again=='y'||again=='Y');
	return 0;
}

#include <iostream>
#include <sstream>
#include <stdexcept>
#include <string>
 
class InvalidConversion : public std::invalid_argument {
public:
    explicit InvalidConversion( const std::string &msg ) :
        std::invalid_argument( msg ) {}
};
 
template <typename T>
T fromString( const std::string &str ) {
    std::stringstream ss( str );
    T result;
 
    if ( ! (ss >> result) )
        throw InvalidConversion( "Can't convert" );
 
    return result;
}
 
int main() {
    int x = fromString<int>( "132" );
    float y = fromString<float>( "3.14159" );
 
    std::cout << x << std::endl;
    std::cout << y << std::endl;
}