View Compilation Error

0_0_15339147_25048.cpp:5:10: error: variable or field 'dfs' declared void
 void dfs(_int64 x)
          ^
0_0_15339147_25048.cpp:5:10: error: '_int64' was not declared in this scope
0_0_15339147_25048.cpp: In function 'int main()':
0_0_15339147_25048.cpp:14:5: error: '_int64' was not declared in this scope
     _int64 n;
     ^
0_0_15339147_25048.cpp:15:16: error: 'n' was not declared in this scope
     while(cin>>n){
                ^
0_0_15339147_25048.cpp:16:24: error: 'dfs' was not declared in this scope
         s.clear();dfs(n);
                        ^