Compilare: user.cpp: In function ‘int getNr()’: user.cpp:44:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(isDigit[c] == 0 && c != '-') ^ user.cpp:54:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(isDigit[c] == 1) ^ user.cpp: In function ‘void refillBuff()’: user.cpp:26:32: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, buffSize, f); ^ user.cpp: In function ‘int firstUnused(int)’: user.cpp:126:1: warning: control reaches end of non-void function [-Wreturn-type] } ^