C ++ Primer Fifth Edition：演習1.9 1.10 1.11

演習1.9

#include<iostream>

int main()
{
    
    
	int sum = 0, val = 50;

	while (val <= 100)
	{
    
    
		sum += val;
		++val;
	}

	std::cout << "Sum of 1 to 10 inclusive is "
		<< sum << std::endl;

	return 0;
}

演習1.10

#include<iostream>

int main()
{
    
    
	int val = 10;

	while (val >= 0)
	{
    
    
		std::cout << val << ' ';
		--val;
	}
	std::cout << std::endl;

	return 0;
}

演習1.11

#include<iostream>

int main()
{
    
    
	int val1, val2;

	std::cout << "Please input two integer:";
	std::cin >> val1 >> val2;

	while (val1 <= val2)
	{
    
    
		std::cout << val1 << ' ';
		++val1;
	}
	std::cout << std::endl;

	return 0;
}