#include <iostream>
#include <limits> //numeric_limits
 
int main()
{
	int Size;
	char c;
	std::cout << "Please enter an integer: ";
	while( !(std::cin >> Size) || ( std::cin.get(c) && c != '\n' ) )
	{
		std::cin.clear(); //clear error flags
		std::cin.ignore( std::numeric_limits<std::streamsize>::max() , '\n' ); //ignore anything left
		//std::cin.ignore( 1024 , '\n' ) or anything large will work too
    	std::cout << "Invalid input. Please try again(integer only): ";
	}
 
	std::cout << "The valid integer entered was: " << Size << std::endl;
}

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