二叉树知道其中俩种遍历输出另一种遍历和建树

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1.知道前序遍历和中序遍历

   

#include<iostream>
#include<vector>
#include<map>
#include<algorithm>
using namespace std;
int pre[] = { 1, 2, 3, 4, 5, 6 };
int in[] = { 3, 2, 4, 1, 6, 5 };
void print(int l1, int r1, int l2, int r2)
{
	if (l1 > r1 || l2 > r2) return;
	int mid = l2;
	while (in[mid] != pre[l1]) mid++;
	print(l1 + 1, l1 + mid - l2, l2, mid - 1);
	print(l1 + mid - l2 + 1, r1, mid + 1, r2);
	cout << pre[l1];
}
int main()
{

	print(0, 5, 0, 5);
	return 0;
}

#include<iostream>
#include<vector>
#include<map>
#include<algorithm>
#include<string>
#include<cstring>
using namespace std;
int pre[] = { 1, 2, 3, 4, 5, 6 };
int in[] = { 3, 2, 4, 1, 6, 5 };
typedef struct node;
typedef node *tree;
struct node
{
	int data;
	tree L;
	tree R;

};
tree bt;
void build(tree &bt,int l1, int r1, int l2, int r2)
{
	if (l1 > r1 || l2 > r2) return;
	int mid = l2;
	while (in[mid] != pre[l1]) mid++;
	bt = new node;
	bt->data = pre[l1];
	bt->L = NULL;
	bt->R = NULL;
	build(bt->L,l1 + 1, l1 + mid - l2, l2, mid - 1);
	build(bt->R,l1 + mid - l2 + 1, r1, mid + 1, r2);
	cout << pre[l1];
}
void print(tree bt)
{
	if (bt) {
		cout << bt->data << endl;
		print(bt->L);
		print(bt->R);
	}
}
int main()
{
	build(bt, 0, 5, 0, 5);
	cout << endl;
	print(bt);
	return 0;
}

2.知道后序遍历和中序遍历

  

#include<iostream>
#include<vector>
#include<map>
#include<algorithm>
#include<string>
#include<cstring>
using namespace std;

int post[] = { 3, 4, 2, 6, 5, 1 };
int in[] = { 3, 2, 4, 1, 6, 5 };
void print(int l1, int r1, int l2, int r2)
{
	if (l1 > r1 || l2 > r2) return;
	int mid = l2;
	while (in[mid] != post[r1]) mid++;
	cout << post[r1] << endl;
	print(l1, l1 + mid - l2 - 1 , l2, mid - 1);
	print(l1 + mid - l2, r1 - 1, mid + 1, r2);

}
int main()
{
	print(0, 5, 0, 5);
}

#include<iostream>
#include<vector>
#include<map>
#include<algorithm>
#include<string>
#include<cstring>
using namespace std;

typedef struct node;
typedef node *tree;
struct node
{
	int data;
	tree L;
	tree R;

};
tree bt;
int post[] = { 3, 4, 2, 6, 5, 1 };
int in[] = { 3, 2, 4, 1, 6, 5 };
void build(tree &bt,int l1, int r1, int l2, int r2)
{
	if (l1 > r1 || l2 > r2) return;
	int mid = l2;
	while (in[mid] != post[r1]) mid++;
	bt = new node;
	bt->data = post[r1];
	bt->L = NULL;
	bt->R = NULL;

	build(bt->L,l1, l1 + mid - l2 - 1 , l2, mid - 1);
	build(bt->R,l1 + mid - l2, r1 - 1, mid + 1, r2);

}
void print(tree bt)
{
	if (bt) {
		print(bt->L);
		print(bt->R);
		cout << bt->data << endl;

	}
}
int main()
{
	build(bt,0, 5, 0, 5);
	print(bt);
}