HDU 5500 Reorder the Books

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<cmath>
using namespace std;
int t,n,ans,maxn,pos;
int num[1000010];
int main()
{
scanf("%d",&t);
for(int i=1;i<=t;i++)
{
maxn=-1e9+7;
scanf("%d",&n);
ans=n-1;
for(int i=1;i<=n;i++)
{
scanf("%d",&num[i]);
if(num[i]>maxn)
{
maxn=num[i];
pos=i;
}
}
for(int i=pos-1;i>=1;i--)
{
if(num[i]==ans)//比较巧
ans--;
}
printf("%d\n",ans);//退格键救不了回车
}
return 0;
}