Compilare: user.cpp: In function ‘void dij(Graph&, int)’: user.cpp:166: warning: comparison between signed and unsigned integer expressions user.cpp:171: warning: comparison between signed and unsigned integer expressions user.cpp:180: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:200: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:201: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:204: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:213: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result