Compilare: user.cpp: In function ‘int search_val(int)’: user.cpp:29:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ht[key].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:79:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, x; ^