#include <iostream>
using namespace std;
int w(long long int a,long long int b,long long int c)
{
	if (a <= 0 || b <= 0 || c <= 0)
		return 1;
	if (a > 20 || b > 20 || c > 20)
		return w(20,20,20);
	if (a < b && b < c)
		return  w(a,b,c-1)+w(a,b-1,c-1-w(a,b-1,c));
	return w(a-1,b,c)+w(a-1,b-1,c)+w(a-1,b,c-1)-w(a-1,b-1,c-1);
}
int main()
{
	long long int a,b,c;
	while(true)
	{
		cin >> a >> b >> c;
		if(a == -1 && b == -1 && c == -1)
			break;
		cout << "w(" << a << ", " << b << ", " << c << ") = ";
		cout << w(a, b, c) << endl;
	 }
	return 0;
}

样例已过，求讲解！！！看到了记得@我哦！谢谢