Compilare: user.cpp: In function ‘void read()’: user.cpp:17: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:19: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void solve()’: user.cpp:30: warning: comparison between signed and unsigned integer expressions user.cpp:35: warning: comparison between signed and unsigned integer expressions user.cpp:42: warning: comparison between signed and unsigned integer expressions user.cpp:43: warning: comparison between signed and unsigned integer expressions