View Compilation Error

0_0_7104243_2738.cpp: In function `void judge()':
0_0_7104243_2738.cpp:53: error: `nd' undeclared (first use this function)
0_0_7104243_2738.cpp:53: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_7104243_2738.cpp: In function `void build(pt*, int, int, int, int)':
0_0_7104243_2738.cpp:63: error: `tree' undeclared (first use this function)
0_0_7104243_2738.cpp: In function `void query(pt, int, int, int)':
0_0_7104243_2738.cpp:73: error: `tree' undeclared (first use this function)