HDD is Outdated Technology

J - HDD is Outdated Technology
Time Limit:1000MS     Memory Limit:262144KB     64bit IO Format:%I64d
& %I64u
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Description

HDD hard drives group data by sectors. All files are split to fragments and each of them are written in some sector of hard drive. Note the fragments can be written in sectors in arbitrary order.

One of the problems of HDD hard drives is the following: the magnetic head should move from one sector to another to read some file.

Find the time need to read file split to n fragments. The i-th sector contains the fi-th
fragment of the file (1 ≤ fi ≤ n). Note different sectors contains the different fragments. At the start the magnetic head is in the position
that contains the first fragment. The file are reading in the following manner: at first the first fragment is read, then the magnetic head moves to the sector that contains the second fragment, then the second fragment is read and so on until the n-th
fragment is read. The fragments are read in the order from the first to the n-th.

It takes |a - b| time units to move the magnetic head from the sector a to the sector b.
Reading a fragment takes no time.

Input

The first line contains a positive integer n (1 ≤ n ≤ 2·105) — the number of fragments.

The second line contains n different integers fi (1 ≤ fi ≤ n)
— the number of the fragment written in the i-th sector.

Output

Print the only integer — the number of time units needed to read the file.

Sample Input

Input

3
3 1 2

Output

3

Input

5
1 3 5 4 2

Output

10

Hint

In the second example the head moves in the following way:

1->2 means movement from the sector 1 to the sector 5, i.e. it takes 4 time units
2->3 means movement from the sector 5 to the sector 2, i.e. it takes 3 time units
3->4 means movement from the sector 2 to the sector 4, i.e. it takes 2 time units
4->5 means movement from the sector 4 to the sector 3, i.e. it takes 1 time units
So the answer to the second example is 4 + 3 + 2 + 1 = 10.

AC代码：
（一）：

#include<stdio.h>
#include<math.h>
#include<algorithm>
#define G 11000000
using namespace std;
struct node
{
int val;
int id;
} a[G+2];
bool cmp(node A,node B)
{
return A.val <B.val ;
}
int main()
{
__int64 n,i;
scanf("%I64d",&n);
for(i=0;i<n;i++)
{
scanf("%d",&a[i].val );
a[i].id =i;
}
sort(a,a+n,cmp);
__int64 sum=0;
for(i=0;i<n-1;i++)
{
sum=sum+fabs(a[i].id-a[i+1].id );
}
printf("%I64d\n",sum);
return 0;
}

（二）：

#include<stdio.h>
#include<math.h>
#include<algorithm>
using namespace std;
int b[300000];

int main()
{
__int64 n;
scanf("%I64d",&n);
for(__int64 i=1;i<=n;i++)
{
__int64 x;scanf("%I64d",&x);
b[x]=i;
}
__int64 ans = 0;
for(__int64 i=1;i<n;i++)
ans+=abs(b[i+1]-b[i]);
printf("%I64d\n",ans);
}