Compilare: user.cpp: In function ‘int main()’: user.cpp:77: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:78: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:79: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result user.cpp:85: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result user.cpp:87: warning: ‘a’ may be used uninitialized in this function user.cpp:80: warning: ‘n’ may be used uninitialized in this function /tmp/ccJd5HCE.o: In function `main': user.cpp:(.text+0x54): warning: the `gets' function is dangerous and should not be used.