View Compilation Error

0_0_2071575_27726.cpp: In function `Tree find(int, int, int)':
0_0_2071575_27726.cpp:113: error: invalid initialization of non-const reference of type 'Tree&' from a temporary of type 'Tree'
0_0_2071575_27726.cpp:114: error: invalid initialization of non-const reference of type 'Tree&' from a temporary of type 'Tree'