听说正解是DP
#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cstdlib>
#include<climits>
#include<queue>
#include<vector>
#include<ctime>
using namespace std;
int n,i,cnt,h[100005],top,pos[100005],ans;
int main()
{
freopen("flower.in","r",stdin);
freopen("flower.out","w",stdout);
scanf("%d",&n);
for(i=1;i<=n;i++)
{
cnt++;
scanf("%d",&h[cnt]);
if(h[cnt]==h[cnt-1])
{
h[cnt]=0;
cnt--;
}
}
for(i=1;i<=cnt;i++)
if(h[i]>h[i-1]&&h[i]>h[i+1])
{
top++;
pos[top]=i;
}
ans=top*2;
if(pos[top]==cnt) ans--;
if(pos[1]!=1) ans++;
printf("%d\n",ans);
return 0;
}