数据结构之 二叉树的储存和遍历总结

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
typedef struct node
{
char data;
struct node *lt, *rt;
}ST;
char str[52];
int flag, num;
ST *creat()
{
ST *root;
if(str[++flag] == ',')
{
root = NULL;
}
else
{
root = (ST *)malloc(sizeof(ST));
root->data = str[flag];
root->lt = creat();
root->rt = creat();
}
return root;
}
void midsort(ST *root)
{
if(root)
{
midsort(root->lt);
printf("%c", root->data);
midsort(root->rt);
}
}
void lastsort(ST *root)
{
if(root)
{
lastsort(root->lt);
lastsort(root->rt);
printf("%c", root->data);
}
}
void headsort(ST *root)
{
if(root)
{
printf("%c", root->data);
headsort(root->lt);
headsort(root->rt);
}
}
void input(ST *root)
{
ST *team[100];
int head, last;
head = 0; last = 0;
team[last++] = root;
while(head < last)
{
if(team[head]){
printf("%c", team[head]->data);
team[last++] = team[head]->lt;
team[last++] = team[head]->rt;
}
head++;
}
}
void leaf(ST *root)
{
if(root)
{
if(!root->lt && !root->rt)
num++;
leaf(root->lt);
leaf(root->rt);
}
}
int deep(ST *root)
{
int max, l, r;
if(root)
{
l = deep(root->lt);
r = deep(root->rt);
if(l > r) max = l;
else max = r;
return max + 1;
}
else return 0;
}
int main()
{
ST *root;
while(~scanf("%s", str))
{
num = 0;
flag = -1;
root = creat();
headsort(root);/*前序输出*/
printf("\n");
midsort(root);/*中序输出*/
printf("\n");
lastsort(root);/*后序输出*/
printf("\n");
input(root);/*层序输出*/
printf("\n");
leaf(root);
printf("%d\n", num);/*输出叶子结点数*/
printf("%d\n", deep(root));/*二叉树深度的求法*/
}
return 0;
}

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
typedef struct node
{
char data;
struct node *lt, *rt;
}ST;
ST *creat(int n, char a[], char b[])
{
ST *root;
int i;
if(n == 0)
return NULL;
root = (ST *)malloc(sizeof(ST));
root->data = a[0];
for(i = 0; b[i]; i++)
if(b[i] == a[0]) break;
root->lt = creat(i, a + 1, b);
root->rt = creat(n - i - 1, a + i + 1, b + i + 1);
return root;
}
void lastsort(ST *root)
{
if(root)
{
lastsort(root->lt);
lastsort(root->rt);
printf("%c", root->data);
}
}
int main()
{
ST *root;
int len;
char a[100], b[100];
while(~scanf("%s %s", a, b))
{
len = strlen(a);
root = creat(len, a, b);
lastsort(root);
printf("\n");
}
return 0;
}

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
typedef struct node
{
char data;
struct node *lt, *rt;
}ST;
ST *creat(int n, char a[], char b[])//后序，中序
{
ST *root;
int i;
if(n == 0)
return NULL;
root = (ST *)malloc(sizeof(ST));
root->data = a[n-1];
for(i = 0; a[i]; i++)
if(b[i] == a[n-1]) break;
root->lt = creat(i, a, b);
root->rt = creat(n - i - 1, a + i, b + i + 1);
return root;
}
void headsort(ST *root)
{
if(root){
printf("%c", root->data);
headsort(root->lt);
headsort(root->rt);
}
}
int main()
{
ST *root;
int t, len, i, j;
char a[55], b[55], t1;
while(~scanf("%d", &t))
{
while(t--)
{
memset(a, 0, sizeof(a));
memset(b, 0, sizeof(b));
scanf("%s %s", b, a);
len = strlen(b);
root = creat(len, a, b);
headsort(root);
printf("\n");
}
}
return 0;
}