Compilare: user.cpp: In function ‘void remove_top()’: user.cpp:27: warning: comparison between signed and unsigned integer expressions user.cpp:29: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void dijkstra(const int&)’: user.cpp:52: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:68: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:69: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:71: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:75: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result