/in/foo.cc: In function 'int calc(int, int, int)':
/in/foo.cc:21:73: error: 'max' was not declared in this scope
   return a[i][j][k] = max(calc(i-v[k], j-g[k],k-1)+c[k], calc(i, j, k-1));
                                                                         ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:29:18: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'int' [-Wformat=]
     scanf("%d", n);
                  ^