Compilare: user.cpp: In function ‘bool isDigit(char)’: user.cpp:24:23: warning: array subscript has type ‘char’ [-Wchar-subscripts] return isSpecial[c] == 1; ^ user.cpp: In function ‘bool isLower(char)’: user.cpp:29:23: warning: array subscript has type ‘char’ [-Wchar-subscripts] return isSpecial[c] == 2; ^ user.cpp: In function ‘bool isUpper(char)’: user.cpp:34:23: warning: array subscript has type ‘char’ [-Wchar-subscripts] return isSpecial[c] == 3; ^ user.cpp: In function ‘int apel(char*)’: user.cpp:105:15: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] *p=NULL; ^ user.cpp: In function ‘int main()’: user.cpp:57:27: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(s,MAX_LINE+1,in); ^ In file included from /usr/include/stdio.h:934:0, from /usr/include/c++/4.8/cstdio:42, from user.cpp:1: In function ‘char* fgets(char*, int, FILE*)’, inlined from ‘int main()’ at user.cpp:57:27: /usr/include/i386-linux-gnu/bits/stdio2.h:253:58: warning: call to ‘__fgets_chk_warn’ declared with attribute warning: fgets called with bigger size than length of destination buffer [enabled by default] return __fgets_chk_warn (__s, __bos (__s), __n, __stream); ^