#include <bits/stdc++.h>
using namespace std;
# define LL long long
const int N = 25;
int f[N][N][N];

int w(LL a,LL b,LL c){
	if(a <= 0 || b <= 0 || c <= 0) return 1;
	if(a > 20 || b > 20 || c > 20) f[a][b][c] = w(20,20,20);
	if(f[a][b][c]) return 0;
	else if(a < b && b < c) f[a][b][c] = w(a,b,c-1)+w(a,b-1,c-1)-(a,b-1,c);
	else f[a][b][c] =  w(a - 1,b,c) + w(a - 1,b - 1,c) + w(a - 1,b,c - 1) - w(a - 1,b - 1,c - 1);
	return f[a][b][c];
	 
}
int main(){
	LL a,b,c;
	while(cin >> a >> b >> c){
		if(a == -1 && b == -1 && c == -1){
			return 0;
		}else{
			cout << "w("<<a<<", "<<b<<", "<<c<<") = "<<w(a,b,c);
		}
	}
} 

样例过了 为啥RE!!!! 求救！