Compilare: user.c: In function ‘main’: user.c:18: warning: array subscript has type ‘char’ user.c:20: warning: array subscript has type ‘char’ user.c:6: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:7: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:10: warning: ignoring return value of ‘gets’, declared with attribute warn_unused_result user.c:11: warning: ignoring return value of ‘gets’, declared with attribute warn_unused_result /tmp/ccQZ1kIs.o: In function `main': user.c:(.text+0x6b): warning: the `gets' function is dangerous and should not be used.