Compilare: user.cpp: In function ‘int main()’: user.cpp:40: warning: unused variable ‘i’ user.cpp:40: warning: unused variable ‘j’ user.cpp:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:43: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:44: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result /tmp/cc3vZbsy.o: In function `main': user.cpp:(.text+0x1a4): warning: the `gets' function is dangerous and should not be used.