《剑指offer》:[60]把二叉树打印成多行

#include <iostream> #include <queue> using namespace std; struct BinaryTree { int data; BinaryTree *pLeft; BinaryTree *pRight; }; BinaryTree *pRoot1=NULL; queue<BinaryTree *> node; void CreateTree(BinaryTree *&root) { int data; cin>>data; if(0==data) root=NULL; else { root=new BinaryTree; root->data=data; CreateTree(root->pLeft); CreateTree(root->pRight); } } void PrintTree(BinaryTree *root) { if(NULL==root) return; node.push(root); int nextlevel=0;//下1层的结点数； int tobePrinted=1;//当前还有几个结点； while(!node.empty()) { BinaryTree *pNode=node.front(); cout<<pNode->data<<" "; if(pNode->pLeft!=NULL) { node.push(pNode->pLeft); nextlevel++; } if(pNode->pRight!=NULL) { node.push(pNode->pRight); nextlevel++; } node.pop();//入队列的速度比出队列的要快； tobePrinted--; if(tobePrinted==0) { cout<<endl;//1行打印完了，所以换行； tobePrinted=nextlevel; nextlevel=0; } } } int main() { CreateTree(pRoot1); cout<<"之字形打印以下："<<endl; PrintTree(pRoot1); cout<<endl; system("pause"); return 0; }