Compilare: user.cpp: In constructor ‘trie::trie()’: user.cpp:11:34: warning: passing NULL to non-pointer argument 2 of ‘void* memset(void*, int, size_t)’ [-Wconversion-null] memset(t, NULL, sizeof(t)); ^ user.cpp: In function ‘int main()’: user.cpp:57:23: warning: unused variable ‘l’ [-Wunused-variable] int r = 2005, l = 0, mid, ret = 0; ^ user.cpp:57:30: warning: unused variable ‘mid’ [-Wunused-variable] int r = 2005, l = 0, mid, ret = 0; ^ user.cpp:57:35: warning: unused variable ‘ret’ [-Wunused-variable] int r = 2005, l = 0, mid, ret = 0; ^