patrate1.cpp: In function 'int main()': patrate1.cpp:69: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result patrate1.cpp:70: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result patrate1.cpp:72: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result patrate1.cpp: In function 'int ok(int)': patrate1.cpp:25: warning: control reaches end of non-void function