View Compilation Error

0_0_22618928_17223.cpp:281:1: error: 'node' does not name a type
 node po[30000];
 ^
0_0_22618928_17223.cpp: In function 'int main()':
0_0_22618928_17223.cpp:296:10: error: 'po' was not declared in this scope
   memset(po,0,sizeof(po));
          ^