question: public EvalStateNodeNumber newSiblingState ( ) { int size = stateNumber . length ; int [ ] num = new int [ size ] ; System . arraycopy ( stateNumber , 0 , num , 0 , size ) ; num [ size - 1 ] = stateNumber [ size - 1 ] + 1 ; return new EvalStateNodeNumber ( num ) ; }
target:  Generates a new sibling node number to the current node.