View Compilation Error

0_0_36352295_14395.cpp: In function 'void dfs2(long long int, long long int)':
0_0_36352295_14395.cpp:44:4: error: 'x' was not declared in this scope
  p[x] = ++dfn;
    ^
0_0_36352295_14395.cpp:50:12: error: 'f' was not declared in this scope
   if (v != f[u] && v != son[u])
            ^