Compilare: user.cpp: In function ‘bool comp(char*, int, int)’: user.cpp:82:22: warning: NULL used in arithmetic [-Wpointer-arith] if(s[ind] == NULL) ^ user.cpp:85:20: warning: NULL used in arithmetic [-Wpointer-arith] if(s[++ind] != NULL) ^ user.cpp: In function ‘bool cmp(ret, ret)’: user.cpp:134:25: warning: NULL used in arithmetic [-Wpointer-arith] if(a.ingr[i] == NULL) ^ user.cpp:136:25: warning: NULL used in arithmetic [-Wpointer-arith] if(b.ingr[i] == NULL) ^ user.cpp: In function ‘int main()’: user.cpp:154:12: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] sir[i] = NULL; ^ user.cpp: In function ‘bool cmp(ret, ret)’: user.cpp:144:1: warning: control reaches end of non-void function [-Wreturn-type] } ^