Compilare: user.cpp: In function ‘void del(std::vector<int>&, int, int)’: user.cpp:25:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=x+1; i<u.size()&&u[i]==u[x]; i++,l2++); ^ user.cpp: In function ‘int main()’: user.cpp:62:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1; i<b.size(); i++){ ^ user.cpp:76:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<b.size(); i++)out<<b[i]<<"\n"; ^