Compilare: user.cpp: In function ‘void scan()’: user.cpp:25: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:26: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void solve()’: user.cpp:51: warning: assuming signed overflow does not occur when assuming that (X - c) > X is always false user.cpp:54: warning: assuming signed overflow does not occur when assuming that (X - c) > X is always false user.cpp:55: warning: assuming signed overflow does not occur when assuming that (X + c) < X is always false