sdmin.cpp: In function 'void ReadData()': sdmin.cpp:39: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result sdmin.cpp:41: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result sdmin.cpp: In function 'int main()': sdmin.cpp:111: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result sdmin.cpp:112: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result