Compilare: user.cpp: In function ‘int main()’: user.cpp:29:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(last4.size()>k) ^ user.cpp:38:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0 ; i <= last4.size()-1; i++) ^ user.cpp:47:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < bst.size(); j++) ^ user.cpp:64:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(biggest<bst.size()) ^ user.cpp:36:23: warning: unused variable ‘utolsolocsi’ [-Wunused-variable] long long int utolsolocsi = 0; ^ user.cpp:20:9: warning: unused variable ‘index’ [-Wunused-variable] int index = 0; ^