books.cpp: In function 'void solve(int, int, long long int, int)':
books.cpp:10:8: error: 'skim' was not declared in this scope
10 | if(skim(1)*3 > 2*A){impossible();}
| ^~~~
books.cpp:10:25: error: 'impossible' was not declared in this scope
10 | if(skim(1)*3 > 2*A){impossible();}
| ^~~~~~~~~~
books.cpp:11:8: error: 'skim' was not declared in this scope
11 | if(skim(N)*K < A){impossible();}
| ^~~~
books.cpp:11:23: error: 'impossible' was not declared in this scope
11 | if(skim(N)*K < A){impossible();}
| ^~~~~~~~~~
books.cpp:14:5: error: 'impossible' was not declared in this scope
14 | impossible();
| ^~~~~~~~~~