cifru1.cpp: In function 'int main()': cifru1.cpp:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result cifru1.cpp:42: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result cifru1.cpp:43: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result cifru1.cpp:46: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result cifru1.cpp:71: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result