Compilare: user.cpp: In function ‘void Solve2()’: user.cpp:130:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( j = 0; j < r && j < v.size(); ++j ) ^ user.cpp:123:13: warning: variable ‘x’ set but not used [-Wunused-but-set-variable] int x = a[i].i; ^ user.cpp: In function ‘void SortU(std::vector<Elev>&)’: user.cpp:188:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( int i = 0; i < a.size(); ++i ) ^