gheizere.cpp: In function 'int main()': gheizere.cpp:80: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result gheizere.cpp:81: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result gheizere.cpp:82: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result gheizere.cpp:83: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result gheizere.cpp:87: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result