seti.cpp: In function 'int main()': seti.cpp:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result seti.cpp:15: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result seti.cpp:18: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result /tmp/ccFVIxI3.o: In function `main': seti.cpp:(.text+0x8a): warning: the `gets' function is dangerous and should not be used.