vector g[100001];
            vector visi(100001, 0);

          //-> in out time of a node
          vector In(100001);
          vector Out(100001);
          ll Time = 1;
          
          void in_out_time(ll v)
          {
              visi[v] = 1;
              In[v] = Time;
              Time++;
              for (ll child : g[v]) {
                  if (visi[child] == 0)
                      in_out_time(child);
              }
          
              Out[v] = Time;
              Time++;
          
          }