View Compilation Error

0_0_33449570_18624.cpp: In function 'void build_Tree(int, int, int)':
0_0_33449570_18624.cpp:38:44: error: 'ro' was not declared in this scope
     tree[root].v=max(tree[2*root].v,tree[2*ro
                                            ^
0_0_33449570_18624.cpp:38:44: error: expected ']' at end of input
0_0_33449570_18624.cpp:38:44: error: expected '}' at end of input