A1119 Pre- and Post-order Traversals (30 分)

#include <iostream>
#include <algorithm>
#include <cstring>
#include <cstdio>
#include <vector>
using namespace std;
const int maxn = 40;
int N;
int pre[maxn], post[maxn];
int in[maxn], num = 0;
int unique(int preL, int preR, int postL, int postR){	
	if(preL > preR) return 0;
	if(preL == preR){
		in[num++] = pre[preL];
		return 1;	
	} 
	int i;
	for(i = postL; i < postR; i++){
		if(post[i] == pre[preL+1]) break;
	}
	int flag = 1;
	flag &= unique(preL+1, preL+1+i-postL, postL, i);
	in[num++] = pre[preL];
	flag &= unique(preL+2+i-postL, preR, i+1, postR-1);
	return flag;
}
int main() {
	scanf("%d", &N);
	for(int i = 0; i < N; i++){
		scanf("%d", &pre[i]);
	}
	for(int i = 0; i < N; i++){
		scanf("%d", &post[i]);
	}
	if(unique(0, N-1, 0, N-1)){
		printf("Yes\n");
	}else{
		printf("No\n");
	}
	printf("%d", in[0]);
	for(int i = 1; i < N; i++){
		printf(" %d", in[i]);
	}putchar('\n');
	return 0;
}