pesti.cpp: In function 'void read()': pesti.cpp:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result pesti.cpp:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result pesti.cpp: In function 'void cer_bc()': pesti.cpp:22: warning: unused variable 'k' pesti.cpp: In function 'void scrie()': pesti.cpp:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result