View Compilation Error

0_0_35669941_30537.cpp: In function 'int find(int)':
0_0_35669941_30537.cpp:9:11: error: 'per' was not declared in this scope
  while(r!=per[r])
           ^
0_0_35669941_30537.cpp:13:2: error: 'per' was not declared in this scope
  per[x]=r;
  ^
0_0_35669941_30537.cpp: In function 'int find(int)':
0_0_35669941_30537.cpp:17:5: error: redefinition of 'int find(int)'
 int find(int x)
     ^
0_0_35669941_30537.cpp:5:5: note: 'int find(int)' previously defined here
 int find(int x)//找根节点 
     ^