Compilare: user.cpp: In function ‘void read()’: user.cpp:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void dijkstra(int)’: user.cpp:57: warning: comparison between signed and unsigned integer expressions user.cpp:73: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void make_new_graph()’: user.cpp:91: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void write()’: user.cpp:217: warning: comparison between signed and unsigned integer expressions