Compilare: user.cpp: In function ‘void baga(Trie*, char*, int, int&)’: user.cpp:68:16: warning: NULL used in arithmetic [-Wpointer-arith] if ( *s == NULL ) { ^ user.cpp: In function ‘int main()’: user.cpp:122:28: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] keep [ l + 1 ] = NULL ; ^ user.cpp:139:31: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] aux [ e + 1 ] = NULL ; ^ user.cpp:166:25: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] sir [ sol + 1 ] = NULL ; ^ user.cpp:174:25: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] sir [ sol ] = NULL ; ^ user.cpp:169:17: warning: unused variable ‘old’ [-Wunused-variable] int old = Solution ; ^