View Compilation Error

0_0_33460485_29054.cpp:2:5: error: 'vector' does not name a type
     vector<int> vv;
     ^
0_0_33460485_29054.cpp:3:5: error: expected unqualified-id before 'while'
     while(n) vv.push_back(n%10),n/=10;
     ^
0_0_33460485_29054.cpp:6:5: error: expected unqualified-id before 'for'
     for(int i=vv.size()-1;i>=0;i--)
     ^
0_0_33460485_29054.cpp:6:27: error: 'i' does not name a type
     for(int i=vv.size()-1;i>=0;i--)
                           ^
0_0_33460485_29054.cpp:6:32: error: 'i' does not name a type
     for(int i=vv.size()-1;i>=0;i--)
                                ^
0_0_33460485_29054.cpp:18:5: error: expected unqualified-id before 'return'
     return ans;
     ^
0_0_33460485_29054.cpp:19:1: error: expected declaration before '}' token
 }
 ^