arrows.cpp: In function 'int main()': arrows.cpp:77: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result arrows.cpp:78: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result arrows.cpp:82: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result arrows.cpp:83: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result arrows.cpp:86: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result arrows.cpp:87: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result