根据后序和中序遍历输出先序遍历

链接： https://pintia.cn/problem-sets/1097067173224390656/problems/1097067227884560393

AC代码：

#include 
#include 
using namespace std;
int s1[35],s2[35],v[35],cnt=0,n;

void dfs(int l,int r) {
	if(l==r) {
		cout<r) {
		return ;
	} else {
		int root,maxn=0,flag;
		for(int i=l; i<=r; i++) {
			if(maxn>n;
	for(int i=1; i<=n; i++) {
		cin>>s1[i];
		v[s1[i]]=k++;
	}
	for(int i=1; i<=n; i++) {
		cin>>s2[i];
	}
	cout<<"Preorder:";
	dfs(1,n);
	return 0;
}