6-11 Level-order Traversal(25 point(s))
Write a routine to list out the nodes of a binary tree in "level-order". List the root, then nodes at depth 1, followed by nodes at depth 2, and so on. You must do this in linear time.
Format of functions:
void Level_order ( Tree T, void (*visit)(Tree ThisNode) );
where void (*visit)(Tree ThisNode)
is a function that handles
ThisNode
being visited by Level_order
, and Tree
is defined as the following:
typedef struct TreeNode *Tree;
struct TreeNode {
ElementType Element;
Tree Left;
Tree Right;
};
Sample program of judge:
#include <stdio.h>
#include <stdlib.h>
#define MaxTree 10 /* maximum number of nodes in a tree */
typedef int ElementType;
typedef struct TreeNode *Tree;
struct TreeNode {
ElementType Element;
Tree Left;
Tree Right;
};
Tree BuildTree(); /* details omitted */
void PrintNode( Tree NodePtr )
{
printf(" %d", NodePtr->Element);
}
void Level_order ( Tree T, void (*visit)(Tree ThisNode) );
int main()
{
Tree T = BuildTree();
printf("Level-order:");
Level_order(T, PrintNode);
return 0;
}
/* Your function will be put here */
Sample Output (for the tree shown in the figure):
Level-order: 3 5 6 1 8 10 9 code:
void Level_order ( Tree T, void (*visit)(Tree ThisNode) ){ Tree q[1000]; Tree p; int head=0,tail=0; if(!T)return; if(T){ q[tail++] = T; while(head!=tail){ p = q[head++]; visit(p); if(p->Left)q[tail++]=p->Left; if(p->Right)q[tail++]=p->Right; } } }//同上一题用队列进行层序遍历