View Compilation Error

0_0_36672256_31785.cpp: In member function 'void JlsSegTree::build(int, int, int)':
0_0_36672256_31785.cpp:62:17: error: no match for 'operator=' (operand types are 'JlsSegTree::tree' and 'node')
         tr[root]=node();
                 ^
0_0_36672256_31785.cpp:62:17: note: candidates are:
0_0_36672256_31785.cpp:15:12: note: JlsSegTree::tree& JlsSegTree::tree::operator=(const JlsSegTree::tree&)
     struct tree{
            ^
0_0_36672256_31785.cpp:15:12: note:   no known conversion for argument 1 from 'node' to 'const JlsSegTree::tree&'
0_0_36672256_31785.cpp:15:12: note: JlsSegTree::tree& JlsSegTree::tree::operator=(JlsSegTree::tree&&)
0_0_36672256_31785.cpp:15:12: note:   no known conversion for argument 1 from 'node' to 'JlsSegTree::tree&&'