Compilare: user.cpp: In function 'llong calc(std::vector<int, std::allocator<int> >)': user.cpp:67: warning: comparison between signed and unsigned integer expressions user.cpp:74: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'void solve()': user.cpp:90: warning: unused variable 'sgn' user.cpp: In function 'llong calc(std::vector<int, std::allocator<int> >)': user.cpp:62: warning: 'xmin' may be used uninitialized in this function user.cpp:62: warning: 'ind' may be used uninitialized in this function