View Compilation Error

0_0_23076616_24170.cpp: In function 'long long int f(int, int, int)':
0_0_23076616_24170.cpp:40:5: error: 'n' was not declared in this scope
  if(n>20||m>20||k>20)
     ^
0_0_23076616_24170.cpp:40:11: error: 'm' was not declared in this scope
  if(n>20||m>20||k>20)
           ^
0_0_23076616_24170.cpp:40:17: error: 'k' was not declared in this scope
  if(n>20||m>20||k>20)
                 ^
0_0_23076616_24170.cpp: In function 'int main()':
0_0_23076616_24170.cpp:73:46: error: 'w' was not declared in this scope
   printf("w(%d, %d, %d) = %d\n",n,m,k,w(n,m,k));
                                              ^