#include<stdio.h>int v[21][21][21]={0};int w(int a, int b, int c){ if(a <= 0 || b <=0 || c <= 0) { return 1; } if(a > 20 || b > 20 || c > 20) { return (w(20,20,20)); } if(v[a][b][c] != 0) { return (v[a][b][c]); } if(a < b && b <c) { return (v[a][b][c] = w(a,b,c-1)+w(a,b-1,c-1)-w(a,b-1,c)); } else { return (v[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; while(scanf("%d %d %d", &a, &b, &c)!=EOF) { if(a==-1 && b==-1 && c==-1) { return 0; } printf("w(%d, %d, %d) = %dn",a,b,c,w(a,b,c)); }}
