atac.cpp: In function 'int main()': atac.cpp:45: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result atac.cpp:46: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result atac.cpp:49: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result atac.cpp:56: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result atac.cpp:82: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result atac.cpp:87: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result