magic2.cpp: In function 'int main()': magic2.cpp:66: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result magic2.cpp:67: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result magic2.cpp:69: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result magic2.cpp:72: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result magic2.cpp:77: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result