View Compilation Error

0_0_37898015_29781.cpp: In function 'void dfsz(int, int)':
0_0_37898015_29781.cpp:11:13: error: 'g' was not declared in this scope
  for(auto y:g[x]){
             ^
0_0_37898015_29781.cpp:11:15: error: 'x' was not declared in this scope
  for(auto y:g[x]){
               ^
0_0_37898015_29781.cpp:14:3: error: 'siz' was not declared in this scope
   siz[u]+=siz[y];
   ^
0_0_37898015_29781.cpp: In function 'void dfs(int, int)':
0_0_37898015_29781.cpp:21:13: error: 'g' was not declared in this scope
  for(auto y:g[x]){
             ^
0_0_37898015_29781.cpp:21:15: error: 'x' was not declared in this scope
  for(auto y:g[x]){
               ^
0_0_37898015_29781.cpp: In function 'void solve()':
0_0_37898015_29781.cpp:31:2: error: 'idx' was not declared in this scope
  idx=0;
  ^