#include <cstdio> #include <cstdlib> #include <cstring> using namespace std; #define INF 0x3f3f3f3f #define MAXN 21 int pool[MAXN][MAXN][MAXN]; int w(int a,int b,int c) { if(a<=0||b<=0||c<=0) return pool[0][0][0]; else if(a>20||b>20||c>20) return w(20,20,20); if(pool[a][b][c]!=INF) return pool[a][b][c]; if(a<b&&b<c) { return pool[a][b][c]=w(a,b,c-1)+w(a,b-1,c-1)-w(a,b-1,c); } else { return pool[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); } } int main() { int a,b,c; int ans; while(scanf("%d %d %d",&a,&b,&c)==3&&!(a==-1&&b==-1&&c==-1)) { memset(pool,0x3f,sizeof(int)*MAXN*MAXN*MAXN); pool[0][0][0]=1; ans=w(a,b,c); printf("w(%d, %d, %d) = %d\n",a,b,c,ans); } return 0; }