Compilare: user.cpp: In function ‘void read()’: user.cpp:11: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:14: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void df(int)’: user.cpp:29: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void df2(int)’: user.cpp:46: warning: comparison between signed and unsigned integer expressions user.cpp:49: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int cel(int)’: user.cpp:56: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void solve()’: user.cpp:71: warning: comparison between signed and unsigned integer expressions user.cpp:75: warning: comparison between signed and unsigned integer expressions user.cpp:86: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int main()’: user.cpp:92: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:93: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result