View Compilation Error

0_0_14107858_7883.cpp: In function 'll dis(int, int)':
0_0_14107858_7883.cpp:29:10: error: 'x' was not declared in this scope
     ll a=x[i]-x[j],b=y[i]-y[j];
          ^
0_0_14107858_7883.cpp:30:16: error: 'b' was not declared in this scope
     return a*a+b*b;
                ^
0_0_14107858_7883.cpp: In function 'void dfs(int)':
0_0_14107858_7883.cpp:36:22: error: expected initializer before '>=' token
     for(int i=pos-1,i>=1;i--) if(!vis[i])
                      ^
0_0_14107858_7883.cpp:36:22: error: expected ';' before '>=' token
0_0_14107858_7883.cpp:36:22: error: expected primary-expression before '>=' token