extraprime.cpp: In function 'void ciur()': extraprime.cpp:6: warning: unused variable 'cnt' extraprime.cpp: In function 'int main()': extraprime.cpp:62: warning: unused variable 'n' extraprime.cpp:57: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result extraprime.cpp:58: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result extraprime.cpp:63: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result