ff.cpp: In function 'int main()': ff.cpp:49: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result ff.cpp:50: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result ff.cpp:53: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result ff.cpp:56: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result ff.cpp:60: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result ff.cpp:63: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result ff.cpp: In function 'double high(POINT, POINT, POINT)': ff.cpp:46: warning: control reaches end of non-void function