View Compilation Error

0_0_24041480_13983.cpp: In function 'void Solve(int, int)':
0_0_24041480_13983.cpp:133:75: error: invalid initialization of non-const reference of type 'vi& {aka std::vector<int>&}' from an rvalue of type 'vi {aka std::vector<int>}'
     auto res = Multiply(vi(dp + l, dp + mid + 1), vi(a + 1, a + r - l + 2));
                                                                           ^
0_0_24041480_13983.cpp:103:5: note: in passing argument 1 of 'vll Multiply(vi&, vi&)'
 vll Multiply(vi & a, vi& b) {
     ^