arrows.cpp: In function 'int main()': arrows.cpp:102: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result arrows.cpp:103: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result arrows.cpp:104: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result arrows.cpp:107: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result arrows.cpp:110: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result