CSU-暑假集训题 C - Two Shuffled Sequences CodeForces - 1144C

题目链接：http://codeforces.com/problemset/problem/1144/C

思路：

就是将序列中个数为2的数字排为升序，剩下的都是降序，如果有个数为3的数字，就输出NO

AC代码

#include<iostream>
#include<algorithm>
using namespace std;
const int MAX=2e5+10;
int a[MAX],b[MAX];
int ans1[MAX],ans2[MAX];
bool cmp(int a,int b){
    return a>b;
}
int main()
{
    int n;
    cin>>n;
    int num,flag=0;
    for(int i=0;i<n;i++)
    {
        cin>>a[i];
        b[a[i]]++;
        if(b[a[i]]==3)flag=1;
    }
    if(flag==1){
        cout<<"NO"<<endl;
        return 0;
    }
    sort(a,a+n,cmp);
    int count1=0,count2=0;
    ans1[count1++]=a[0];
    for(int i=1;i<n;i++)
    {
        if(a[i]==a[i-1])
        {
            ans2[count2++]=a[i];
        }else ans1[count1++]=a[i];
    }
    cout<<"YES"<<endl;
    cout<<count2<<endl;
    for(int i=count2-1;i>=0;i--)cout<<ans2[i]<<" ";
    cout<<endl;
    cout<<count1<<endl;
    for(int i=0;i<count1;i++)cout<<ans1[i]<<" ";
    return 0;
}