leetcode:Populating Next Right Pointers in Each Node
/**
*Definitionforbinarytreewithnextpointer.
*structTreeLinkNode{
*intval;
*TreeLinkNode*left,*right,*next;
*TreeLinkNode(intx):val(x),left(NULL),right(NULL),next(NULL){}
*};
*/
classSolution{
public: