#include <iostream>
#include <bits/stdc++.h>
 
using namespace std;
 
void frog_1(vector<int>&dp,vector<int>&arr){
  int n=arr.size();
  dp[0]=0;
  dp[1]=abs(arr[1]-arr[0]);
 
  for(int i=2;i<n;i++){
    dp[i]=min(dp[i-1]+abs(arr[i]-arr[i-1]),dp[i-2]+abs(arr[i]-arr[i-2]));
  }
}
int main(){
  int n;
  cin>>n;
  vector<int>arr(n);
 
  for(int i=0;i<n;i++){
    cin>>arr[i];
  }
  vector<int>dp(n);
  frog_1(dp,arr);
  cout<<dp[n-1]<<endl;
  return 0;
}

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