#include<bits/stdc++.h>
using namespace std;
int w(int a,int b,int c)
{
	if(a<=0||b<=0||c<=0)return 0;
	else if(a>=20||b>=20||c>=20)return -1;
	else if(a<b&&b<c){
		return w(a, b, c - 1) + w(a, b - 1, c - 1) - w(a, b - 1, c);
	}else{
		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()
{
	int a,b,c;
	
	while(1){
		cin>>a>>b>>c;
		if(a==-1&&b==-1&&c==-1){
			break;
		}
		if(w(a,b,c)==-1){
			cout<<"w("<<20<<", "<<20<<", "<<20<<")";
			continue;
		}
		cout<<"w("<<a<<", "<<b<<", "<<c<<")="<<w(a,b,c);
	}
	return 0;
}

我这一题输什么数值输出都是0 大神们帮我看看有什么问题谢谢