Compilare: user.cpp: In function ‘void read()’: user.cpp:37: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:42: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void solve()’: user.cpp:76: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void dijkstra()’: user.cpp:101: warning: comparison between signed and unsigned integer expressions user.cpp:105: warning: comparison between signed and unsigned integer expressions