CodeForces - 27C

題意：再給定的序列中找出一組最短的無序子序列

#include<iostream>
#include<algorithm>
#include<string>
#include<cstring>
#include<map>
#include<queue>
#include<cmath>
#include<stack>
#include<vector>
#include<cstdio>
#define MAXN 33000
#define INF 0x3f3f3f3f
#define lmid l,m,rt<<1
#define rmid m+1,r,rt<<1|1
#define ls rt<<1
#define rs rt<<1|1
#define Mod 1000000007
#define i64 __int64
#define LIMIT_ULL 100000000000000000
using namespace std;
i64 s[100005];
int main()
{
     int n;
     scanf("%d",&n);
     for(int i=1;i<=n;i++)
          scanf("%I64d",&s[i]);
     for(int i=2;i<n;i++)
     {
          if((s[i+1]-s[i])*(s[i]-s[1])<0)
          {
               //cout<<(s[i+1]-s[i])*(s[i]-s[1])<<endl;
               cout<<3<<endl;
               cout<<1<<" "<<i<<" "<<i+1<<endl;
               return 0;
          }
     }
     cout<<0<<endl;
}