@[tlnllkbp](/space/show?uid=106177)
```cpp
#include <iostream>
int main(){int n,i,j,a[20];std::cin>>n;for(i=1;i<n;++i) std::cin>>a[i];for(i=1;a[i++];); j=i-1&1;for(i=n;a[i--];); puts((n-i&1|!j)?"YES":"NO");}
```
by FP·荷兰猪 @ 2018-07-30 12:26:08
```
#include<cstdio>
main(){int n,i=1,j,a[20];scanf("%d",&n);for(;i<n;) scanf("%d",&a[i++]);for(i=1;a[i++];);j=i-1&1;for(i=n;a[i--];);puts((n-i&1|!j)?"YES":"NO");}
```
by 「已注销」 @ 2018-07-30 12:48:50
```
#include<iostream>
int i,j,n,a[20];int main(){std::cin>>n;for(;i<n;)std::cin>>a[++i];for(i=1;a[i++];);j=i-1&1;for(i=n;a[i--];);puts((n-i&1|!j)?"YES":"NO");}
```
by bh1234666 @ 2018-07-30 12:55:57
```cpp
#include<iostream>
int i=1,x,n,p,q;main(){std::cin>>n;for(;i<=n;++i){std::cin>>x;if(!x&&(p=i)&&!q)q=i;}puts((q-1|n-p)&1?"YES":"NO");}
```
by star_city @ 2018-10-14 11:17:37
```cpp
#include<bits/stdc++.h>
using namespace std;
#define maxn 25
int n,a[maxn],s1=0;
int main(){
cin>>n;
for(int i=1;i<=n;i++){
cin>>a[i];
if(!a[i]) s1++;
}
if(s1%2==1&&s1!=n) cout<<"YES";
else cout<<"NO";
return 0;
}
了解一下？
```
by Achtoria @ 2018-10-30 12:36:38
111B
```cpp
#include"iostream"
int main(){int a,b,c;std::cin>>a;while(a--)std::cin>>b,c+=b>0;std::cout<<(c%2?"YES":"NO");}
```
by Dongshi @ 2022-03-06 21:21:57