//太难了，没看懂

//可以参考https://zhanglong.blog.csdn.net/article/details/104831434?utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7EOPENSEARCH%7Edefault-3.readhide&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7EOPENSEARCH%7Edefault-3.readhide 

//栈的知识 http://c.biancheng.net/view/478.html

#include <cstdio>
#include <stack> 
#include <iostream>
using namespace std;
const int MAXN = 1000 + 10;

int n , target[MAXN];

int main(){
	while(scanf("%d", &n) == 1){
	stack<int> s;
	int A = 1, B = 1;
	for(int i = 1; i <= n; i++)
		scanf("%d", &target[i]);
		int ok = 1;
		while(B <= n){
			if(A == target[B]) {A++; B++;
			}
			else if(!s.empty() && s.top() == target[B])
			{
				cout <<"the top is " << s.top() << endl;
				s.pop();
				 B++;
			}
			else if(A <= n) {
			s.push(A++);
				cout << "the push is " << s.top() << endl;
				
			}
			else {
				ok = 0;
				break;
			}
			
		}printf("%s\n", ok ? "Yes" : "No");
	} 
	return 0;
}