Compilare: user.cpp: In function ‘int main()’: user.cpp:17: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:18: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:22: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result user.cpp:25: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result user.cpp:37: warning: ‘r’ may be used uninitialized in this function /tmp/ccpyHfe7.o: In function `main': user.cpp:(.text+0xf0): warning: the `gets' function is dangerous and should not be used.