Compilare: user.cpp: In function ‘bool exist(int)’: user.cpp:16:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<Hash[x%M].size();i++) ^ user.cpp: In function ‘void sterge(int)’: user.cpp:29:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<Hash[x%M].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:40:11: warning: unused variable ‘t’ [-Wunused-variable] int i,t; ^