Compilare: user.cpp: In function ‘void read()’: user.cpp:14: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:15: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int search(int)’: user.cpp:31: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void dijkstra(int)’: user.cpp:45: warning: comparison between signed and unsigned integer expressions