http://acm.hdu.edu.cn/showproblem.php?pid=1394
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<math.h>
#include<iostream>
#include<algorithm>
using namespace std;
const int sizen=100000;
int arr[sizen];
int main()
{
int n;
int i,j;
int sum;
int minn;
int x;
while(scanf("%d",&n)!=EOF)
{
sum=0;
for(i=0;i<n;i++)
scanf("%d",&arr[i]);
for(i=0;i<n;i++)
for(j=i+1;j<n;j++)
if(arr[i]>arr[j])
sum++;
minn=sum;
for(i=0;i<n-1;i++)
{
x=arr[i];
sum-=x;
sum+=(n-1-x);
// cout<<sum<<endl;
if(minn>sum)
minn=sum;
}
printf("%d\n",minn);
}
return 0;
}