【题解】车厢调度(train)

#include<bits/stdc++.h>
using namespace std;
stack<int>stk;
int main(){
	int n,a[1000];
	cin>>n;
	for(int i=1;i<=n;++i)
		cin>>a[i];
	int i=1,b=1;
	while(i<=n&&b<=n+1){
		if(stk.empty()==false&&a[i]==stk.top()){
			i++;
			stk.pop();
		}
		else{
			stk.push(b++);
		}
	}
	if(i>n){
		cout<<"YES";
	}
	else{
		cout<<"NO";
	}
}