sprime.cpp: In function 'int main()': sprime.cpp:27: warning: unused variable 'ok' sprime.cpp:28: warning: unused variable 'b' sprime.cpp:28: warning: unused variable 'e' sprime.cpp:7: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result sprime.cpp:8: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result sprime.cpp:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result