View Compilation Error

0_0_26625187_29097.cpp:4:1: error: 'vector' does not name a type
 vector<int> paret[510];
 ^
0_0_26625187_29097.cpp: In function 'int Ask(int)':
0_0_26625187_29097.cpp:7:18: error: 'paret' was not declared in this scope
     int i, len = paret[pos].size();
                  ^
0_0_26625187_29097.cpp: In function 'void dfs(int, int)':
0_0_26625187_29097.cpp:21:23: error: 'max' was not declared in this scope
     ans = max(ans, num);
                       ^
0_0_26625187_29097.cpp:23:31: error: 'memset' was not declared in this scope
     memset(vis, 0, sizeof(vis));
                               ^