백준 11382 c++

#include <iostream>
using namespace std;

int main(void)
{
	unsigned long long a, b, c;
	cin >> a >> b >> c;
	if ((a >= 1 && a <= 1000000000000) && (b >= 1 && b <= 1000000000000) && (c >= 1 && c <= 1000000000000))
	{
		cout << a + b + c << endl;
	}
	return 0;
}