for STEP 2 of Kosaraju 's Algorithm
void dfsSecond ( int u ) { if ( visitedInv [ u ] ) return ; visitedInv [ u ] = 1 ; for ( int i = 0 ; i < adjInv [ u ] . size ( ) ; i ++ ) dfsSecond ( adjInv [ u ] [ i ] ) ; scc [ u ] = counter ; }