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:41: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:48: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int rad(int)’: user.cpp:69: warning: statement has no effect user.cpp: In function ‘void pre()’: user.cpp:113: warning: unused variable ‘cos’ user.cpp: In function ‘void solve()’: user.cpp:157: warning: comparison between signed and unsigned integer expressions user.cpp:167: warning: comparison between signed and unsigned integer expressions