Borderou de evaluare (job #325670)

Eroare de compilare: In file included from /usr/include/c++/4.6/algorithm:63:0, from user.cpp:3: /usr/include/c++/4.6/bits/stl_algo.h: In function ‘_RandomAccessIterator std::__unguarded_partition(_RandomAccessIterator, _RandomAccessIterator, const _Tp&, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator<std::pair<int, int>*, std::vector<std::pair<int, int> > >, _Tp = std::pair<int, int>, _Compare = bool (*)(std::pair<int, int>&, std::pair<int, int>&)]’: /usr/include/c++/4.6/bits/stl_algo.h:2265:78: instantiated from ‘_RandomAccessIterator std::__unguarded_partition_pivot(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator<std::pair<int, int>*, std::vector<std::pair<int, int> > >, _Compare = bool (*)(std::pair<int, int>&, std::pair<int, int>&)]’ /usr/include/c++/4.6/bits/stl_algo.h:2306:62: instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator<std::pair<int, int>*, std::vector<std::pair<int, int> > >, _Size = int, _Compare = bool (*)(std::pair<int, int>&, std::pair<int, int>&)]’ /usr/include/c++/4.6/bits/stl_algo.h:5445:4: instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator<std::pair<int, int>*, std::vector<std::pair<int, int> > >, _Compare = bool (*)(std::pair<int, int>&, std::pair<int, int>&)]’ user.cpp:38:31: instantiated from here /usr/include/c++/4.6/bits/stl_algo.h:2233:4: error: invalid initialization of reference of type ‘std::pair<int, int>&’ from expression of type ‘const std::pair<int, int>’ /usr/include/c++/4.6/bits/stl_algo.h:2236:4: error: invalid initialization of reference of type ‘std::pair<int, int>&’ from expression of type ‘const std::pair<int, int>’