Compilare: user.cpp: In function ‘int main()’: user.cpp:40: warning: comparison between signed and unsigned integer expressions user.cpp:42: warning: comparison between signed and unsigned integer expressions user.cpp:55: warning: comparison between signed and unsigned integer expressions user.cpp:83: warning: comparison between signed and unsigned integer expressions user.cpp:36: warning: unused variable ‘n’ user.cpp:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:39: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result /tmp/cchyw7BV.o: In function `main': user.cpp:(.text+0x193): warning: the `gets' function is dangerous and should not be used.